Saturday, September 24, 2022

In North Korea Thousands of Guns Point to the Sky

North Korea has the densest network of air defense sites in the world, and their mix of low-level anti-aircraft artillery (AAA) systems, Soviet-era surface-to-air missile (SAM) bases, and early warning radars still pose a risk to adversaries. 

An M-1983 Quad 14.5 mm anti-aircraft gun being shown during a parade in this undated image.

Between the AAA and SAM batteries, over 1,500 fixed air-defense sites are arrayed to protect North Korean airspace (squeezed into an area half the size of England). 

In this article I will focus on the current capabilities of the county's anti-aircraft artillery, but I'll also touch on their surface-to-air missiles as well.

Under the control of the KPA Air Defense Command and Pyongyang Antiaircraft Artillery Command, North Korea's AAA defense are made up of M-1983 Quad 14.5 mm guns, ZU-23-2 twin barrel autocannons, M-1992 Twin 30 mm autocannons, and M-1992 Twin 37 mm self-propelled guns.

These guns have a practical rate of fire of between 150 and 1,600 rounds per minute per barrel, with effective ranges of 2.5 to 5.8 km depending on which system is being used. 

AAA batteries are typically laid out in two arrangements, the "daisy" and what I call the "I".

Example of the "daisy" layout.

Daisy arrangements refer to a circular configuration of guns. They range in size from 4 to 12 guns and may form a "chain" of daisies, with 2-3 sets of four guns each or they may simply be a single circle of guns. 

According to George Herbert, adjunct professor at the James Martin Center for Nonproliferation Studies, AAA guns in this arrangement lie within a targeted environment (such as near the Yongbyon Nuclear Center) and can protect it from threats coming in from any direction.

Example of the "I" layout.

The second primary arrangement for AAA guns is "I". These are just a single straight line of guns. All but one of the "I" layout sites deploy 8 guns.

Mr. Herbert explains that this arrangement is best for firing at aircraft that still lie outside of the main target, such as on the approaches to Pyongyang, but before they actually enter the city's airspace, and can concentrate the fire from multiple guns onto the enemy aircraft.

There are 70 of these surrounding Pyongyang in an oval ring 25-30 km outside of downtown.

A Layered Defense

The country's air defense is constructed using a layered approach. The DMZ and each coast has a line of AAA batteries along them with the main coastal cities then being encircled by their own ring of defenses. Interspersed in other parts of the country are the batteries for major KPA bases, navy and air bases, missile sites, industrial centers, and key palaces. There are also a few others scattered around the country at seemingly random sites. 

Nowhere is this layered defense more obvious than at Pyongyang.

As the nation's capital city, Pyongyang is the largest population center, is where all of the main military command centers are located, and it contains the greatest concentration of industry making its capture a primary goal in any war.

Pyongyang has over 400 AAA batteries arrayed in three main lines of defense, and it is also protected by two outer rings of 19 surface-to-air missile batteries as well.

Illustrative map of the main AAA and SAM defensive ranges (approximate distances) around Pyongyang, with the Ryongsong Palace highlighted in blue. The yellow ring is the palace's dedicated air defense ring.

Within Pyongyang is also the Ryongsong Palace complex. Nestled within Pyongyang's air defense space, the palace is surrounded by its own dedicated ring of AAA batteries and is covered by at least 5 nearby SAM batteries, making the palace perhaps the most well-defended single site in the world.

Other areas that enjoy substantial air defense are Nampo, Sariwon, the Yongbyon Scientific Nuclear Research Center, Haeju, Kaesong, Wonsan (which is also home to a Kim palace), Hamhung, Kanggye, Chongjin, Tokchon, and the elite Samjiyon-Mt. Paektu area.

All of these overlapping clusters also end up creating a thicket of AAA sites within the "Kaesong-Munsan" invasion corridor. This would be the most contested stretch of airspace as it is the most direct path from connecting the capitals of North and South Korea. The corridor is roughly 50 km wide and 155 km long, stretching from the DMZ up to Pyongyang. 

Map of invasion routes including the two Kaesong approaches. Image: Marine Corps Intelligence Activity, North Korea Country Handbook, May 1997.

In any given 5 km circle (the maximum range of most AAA guns) a pilot would only have three, perhaps four, brief moments where they weren't in range of any guns if they were flying through the center of the corridor. Of course, where AAA may not reach there are still the dozen+ SAM sites that lie within the corridor and whose ranges are between 25 and 300 km depending on the missile system being used.

Point to the Sky

Nationwide, North Korea currently has 1,463 active AAA sites. These batteries have the capacity to field 8,641 individual artillery pieces. Each battery consists of anywhere between a single gun to up to 12 guns. The majority fall in the 6-8 gun range. Not every fixed position has a gun in it at all times, but around 90% do. This means that at any given moment there are 7,777 artillery pieces ready to fire.

There are also 521 known decommissioned sites. Having decommissioned sites mapped is important, particularly within the public sphere, in order to have accurate maps available. Many of these older sites haven't been demolished, merely closed, and so they still look like they could be used. That has led to some of them being incorrectly identified as active on other databases (like OpenStreetMap and Wikimapia).

Additionally, knowing when sites are closed or newly constructed allows researchers to better track trends in air defense strategies (among other things).

Surface-to-Air Missiles

Map of current SAM positions.

The country also maintains between 57 and 61 surface-to-air missile batteries, with two of them being modern constructions. Most field S-25, S-75, and S-125 systems that are from the Soviet-era. North Korea has attempted to develop their own SAM systems with the KN-06 and KN-30 which are clones of Russian S-300 and S-400 SAMs. However, despite being promoted in official state media, these mobile systems haven't yet been verified to have been fully deployed through open-source imagery and publications.

If they are being used, they would most likely first be sent to the new SAM batteries constructed at Wonsan (39° 7'16.21"N 127°44'16.26"E) and near the town of Haeju (38° 5'28.79"N 125°27'2.18"E).

Between AAA and SAM sites, approximately 75% of all of North Korea's airspace is covered using conservative measurements. The largest gaps in coverage are in the highly mountainous border areas with China and access to those gaps would require either flying in from China or making it through already defended areas.

An updated explorable map of North Korea's air defense sites is available through purchase of the AccessDPRK Map (Pro Version)

I would like to thank my current Patreon supporters: Amanda O., GreatPoppo, Joel Parish, John Pike, Kbechs87, Russ Johnson, Squadfan, and ZS. 

--Jacob Bogle, 9/23/2022

Friday, August 19, 2022

Archeology in North Korea

I have written about the "lost history of Korea" before but I wanted to give an update as the original article is now eight years old and I've made a lot of mapping progress since then.

With the artificial division of Korea in 1945, both sides will have developed distinct modern archeological histories as the two sides have grown more and more distinct. But this division also left thousands of years' worth of joint Korean history within the confines of North Korea. As a result, numerous sites are largely unknown to the English-speaking world and much of the archeological research that was done prior to the division was done while Korea was under Japanese occupation, making it outdated and its results subject to the Imperial ideology of the day. Likewise, any research done in North Korea subsequently will be tainted by the current government's ideological narratives; and there are serious questions about the quality and reliability of North Korean archaeology as a practice. 

Most North Korea watchers are aware of some of the major archeological sites in the country. The ancient capital of Kaesong and the Royal Tomb Complex of the Koguryo Dynasty - both UNSECO World Heritage Sites. There's also religious relics around Mt. Myohyang, pieces and pavilions of the wall that once encircled Pyongyang, and the alleged tomb of Tangun, the legendary founder of Korea.

North Korea has a list of 193 sites designated as National Treasures, with these including major tombs, fortresses, temples, pagodas, and other tangible sites. There is also a list of 1,800 other culturally important items such as steles and sites that no longer exist. Unfortunately, most of these lack exact locations and are also small objects (steles and stone pagodas may not be visible at all by satellite), and so most of these locations have gone unmapped by AccessDPRK but I have endeavored to locate the ones possible.

Through the work for AccessDPRK, I've noted well over 400 historic sites. Additionally, I have located over 900 large burial mounds. Most of the burial mounds will date to before 1910 and could hold troves of valuable cultural, religious, and political history going back generations.

While many of these locations will likely be known to Korean historians and archeologists, most will not be known to English speakers and there's very little information about them in English. 

I've been able to map enough sites, that the paths of major walls become very visible and the map is sprinkled with smaller finds as well.

In the above image, the paths of large defensive walls can be seen. These stone walls date to the early 11th century and in some parts have substantial remains. The walls originally extended across the whole peninsula but their remains along the mountainous spine of Korea have eroded to such an extent that they can't be mapped using the available satellite imagery. However, a series of forts still remain and their locations can help us chart the original path of the walls.

Various fortified sites near the city of Sinuiju in North Pyongan Province.

Other light blue splotches on the image are the larger forts and walled cities that still have obvious ruins like the fortress walls of Anak (with the Goguryeo Anak Tombs nearby) and the city walls of Kuup-ri south of Wonsan.

One other thing I want to focus in on that's noted on the earlier map is a network of what I have surmised are a series of animal corrals/pens. These are complexes of low stone walls that create large, interconnected enclosures that have small circular paddocks interspersed between the larger enclosures. The enclosed areas are irregular in shape and can encompass several square kilometers, while the circular paddocks are only around 70 meters in diameter and are fairly consistent in shape and size.

I have been able to locate over 172 km worth of enclosure walls within these three areas.

Close-up view of an enclosure wall.

Example of a circular paddock.

I have reviewed nearby areas in China and Russia to try to find additional sites, but these three complexes are the only ones I have discovered. No others seem to exist in North Korea either.

They share certain similarities with ancient hunting or livestock control systems in other parts of the world, but the precise nature of the paddocks also makes me think they could be 19-20th century creations.

I haven't been able to find any information at all about these sites and would love the input of a Korean archeologist or historian. Are these even known about?

Beyond fortified sites and old animal pens, North Korea is filled with burial mounds and religious locations.

These burial mounds are not modern and are not part of the mass graves related to the 1990s famine.
With over 900 of them located, one thing that becomes immediately obvious is the huge concentration of them within South Hwanghae Province and the west coast of South Pyongan Province. 

There are smaller clusters around Kaesong and Pyongyang, both historic capitals of Korea, and there are individual mounds throughout the rest of the country, but South Hwanghae has over one third of all of these large burial mounds. 

Among the burial mounds are well-known sites like the Royal Tombs of the Goryeo Dynasty in Kaesong which span nearly 5 centuries, and the Han Dynasty tombs next to the April 25 Film Studio in Pyongyang, reflecting a time when China directly controlled parts of Korea and held influence over the rest of the country.

But many other historic tombs within North Korea are not the tombs of emperors or Chinese dignitaries. They belong to members of the lesser nobility, large landowning families, and possibly even important local merchants up to the point that Korea was divided.

Examples of various large burial mounds from around the country.

Although there is a tendency within communism to destroy the past, and every country within the former Soviet Union and throughout the rest of the communist world engaged in cultural "cleansing" efforts, these burial mounds have managed to survive and are even maintained by local authorities. 

Pyongyang vilifies 20th century landowners and the imperial system of Korea's monarchy, but they still rely on ties to the ancient past to legitimize the Kim family and their right to rule. So, while plenty of places have been neglected (and many more destroyed during the Korean War), one can still find numerous examples of that past throughout the country. 

Some of the remaining temple sites in North Korea.

Buddhism came to Korea in the 3rd century. One of the oldest temples in North Korea is the Anguk Temple (39°18'2.00"N 125°49'35.00"E) which was founded in 503, and it's listed as National Treasure #34. Unfortunately, like many of the approximately 400 temples in northern Korea at the time, it was destroyed by allied bombing in the war. 

Kim Il Sung's suppression of religion was also responsible for the abandonment of numerous religious institutions, continuing a long decline within Korean Buddhism and attacking ascendant religions like Chondosim and Christianity. However, surviving sites have been maintained as cultural relics and some important locations have even been reconstructed such as Anguk Temple, with at least one Catholic abbey building surviving as part of the Wonsan University of Agriculture.

These "relics" include popular tourism sites such as those within the Kumgang Mountain region and Mount Myohyang, while others are tucked away in difficult to access forests. The Wonmyong Temple near Huichon is one such example (it, too, was reconstructed after 2000).

Wonmyong Temple, April 17, 2022.

Within the AccessDPRK 2021 Map are also sites that could be part of not just Korean history, but the history of the whole region.

I have noted 16 potential hillforts. These irregularly shaped piles of stone and rubble are similar in appearance to Celtic oppidia in Europe and other such fortifications elsewhere. Although dating can't really be done by just looking at satellite imagery, if they are early fortifications, their history could go back to the Three Kingdoms Period or even earlier.

Ditch and rampart fortification at 38°38'54.41"N 127°28'58.53"E (11 km east of Sepo) with some modern structures inside the perimeter.

Another hillfort example. This one is near Punggye-ri at 41° 8'52.23"N 129°12'49.61"E.

The future of archeology in North Korea depends entirely on the government cooperating with outside organizations and academic communities to bring the richness of this history to the world's eyes. And, whenever the Kim regime does fall away, archeology will have decades of additional material to look at. 

Researchers will need to look at mass graves to determine the extent of famines and public executions. They will need to go to disappeared prisons to give voice to the thousands of lives that were destroyed in them and to verify the crimes committed by the government. They will also have the mass human activity of monument and palace building (and removal) as a means to track the path of propaganda and its impact on people's lives and the economy.

Until then, most of us in the outside world will only have satellite images to peer into thousands of years' worth of history.

In the spirit of openness and furthering our collective knowledge, the historic sites are available in the Free Version of the 2021 AccessDPRK Map (KMZ file). If any knowledgeable person has verifiable information about the sites, please get in touch with me.

I would like to thank my current Patreon supporters: Amanda O., GreatPoppo, Joel Parish, John Pike, Kbechs87, Russ Johnson, Ryan Little, and ZS. 

--Jacob Bogle, 8/20/2022

Friday, July 22, 2022

Tunnels to Nowhere

AccessDPRK's last article examined some of the largest underground facilities in the country. In keeping with the underground theme, I want to take a look at some of the more enigmatic tunnels in North Korea.

Plenty of the country's tunnels are part of factories, missile bases, or nuclear sites, but there are a few tunnels that seem to go nowhere. Maybe they're for storage, maybe they're part of secret escape routes for the Kims, we just don't know what they're really for.

In this article I will examine four of these "tunnels to nowhere" and in doing so, will hopefully shed a little more light on their existence and their nature.

Taenoŭn-san (41°57'34.23"N 128°41'37.13"E)

Google Earth image of vehicle entering the tunnel on Sept. 19, 2019.

The Taenoŭn-san tunnel near the Chinese border is one of the most recent to come to light. It was first mentioned by Nathan Hunt on Twitter on Jan. 20, 2020 but it has never been described through public intelligence channels, and so its purpose remains speculative.

Based on imagery from Landsat, the tunnel was constructed in 2016 but it didn't show up on Google Earth until late 2019 with an image dated Sept. 19, 2019. In that image, a vehicle can be seen entering the tunnel.

It has not been positively identified in the public sphere, but one possibility is that it could be a TEL/MEL with two missile launch canisters. A vehicle can also be seen on an image from Sept. 11, 2021.

The tunnel enters a small mountain from a river valley and has no exit point. The entrance is around 10 meters wide and access comes in the form of a dirt road. The road does not directly lead to any nearby military base. There are also no obvious security measures such as a gatehouse to the entrance or perimeter fence. 

This could be, in part, due to its remote location within Ryanggang Province (only 6 km from the Chinese border) making accidental discovery by locals almost impossible as a result of the travel restrictions in place within the country. Joy riding and exploring simply aren't part of the North Korean experience as it is in other countries.

Some theories as to its purpose is that it's a storage site or, perhaps, even part of North Korea's second-strike capacity - allowing the country to hide short-to-medium range ballistic missile TELs/MELs in a hardened site that could withstand an initial strike by an enemy, enabling North Korea to still launch missiles even after the primary launch sites have been destroyed. At this point, it's all speculation. 

Although the entrance is 10-meters wide, the state of the access road (a winding dirt path) would prevent the tunnel's use by ultra-large vehicles such as North Korea's giant 11-axl TEL for the Hwasong-17 ICBM.

Pyongyang-Sunan Tunnel (39°11'38.84"N 125°45'13.77"E)

This tunnel is located within the Sunan guyok (district) within the city of Pyongyang. It is less than 1.5 km from the Kim Jong-il Peoples' Security University and is within 5 km of six major military sites including a large storage complex, the Kim Jong-un National Defense University, and the Second Academy of Natural Sciences which is a major missile fabrication facility. Of course, direct association with any of those sites has yet to be ascertained. 

Construction on the tunnel began around April 2017 and went through to April/May 2019. The tunnel's entrance is around 11 meters in width. The access road is compacted dirt but that then turns into a paved area ~33 meters long as it approaches the entrance.

Some images have what appears to be framing to hold a tarpaulin or camouflaged netting. On an image dated April 11, 2019, the tunnel looks to be covered by the netting.

The complex also has an access tunnel, likely for maintenance, that's large enough for small vehicles to enter.

There is a spoils pile from the tunnel excavation along the southern side of the road that extends for ~140 meters. It varies in width from 10 meters to as wide as 16 meters. If we use an equal width of 10 meters and give it an assumed height of 3 meters, then the total volume of excavated material can be estimated to be 4,200 m3

This would allow for a tunnel that's around 95 meters long, 11 meters wide, and 4 meters high.

Onsong Tunnel (42°54'47.37"N 129°56'38.90"E)

Google Earth image of the tunnel dated March 10, 2022.

In the village of Ryongnam-ri within Onsong County a tunnel was constructed beginning in late 2017 and it was completed in mid-2019. There's nothing particularly interesting about Ryongnam-ri, especially from a military perspective, yet this tunnel is well protected by a berm and may even have a small blast shield located across from the tunnel opening.

Like the tunnel in Taenoŭn-san, it is 9-10 meters in width, however, no vehicles are visible in the available imagery from Google Earth. If the spoils pile is representative of the majority of the material removed for the tunnel's construction, it's unlikely that it extends more than 100 meters into the hillside.

The tunnel isn't connected to any obvious construction elsewhere in the area and seems to be 'randomly' placed at the rural village. Depending on which direction you travel from the tunnel, it's only 6 to 7 km away from the Chinese border.

Militarily, there's nothing especially interesting about Onsong County. It has a single air-defense site that protects the Wangjaesan Grand Monument and there's a small training base located 6 km northwest of the tunnel. Otherwise, the nearest important military installations are over 50 km to the south. 

There does seem to be a fence guarding access to the site, but it is situated next to civilian buildings and is not within a military base, making its purpose more difficult to identify.

Secret Road Tunnel (39°52'2.70"N 126°22'29.58"E)

This last tunnel is the oldest on the list and is, to me, to most unusual.

Located 13 km north of the city of Tokchon, the nearest populated place is a village called Sinphung-ri. 

The tunnel is a road that enters a hill and then disappears. The road is connected to a network of roads within a valley with only two entry/exit points, both of which can be blocked off. The valley contains military sites and other facilities that don't match the typical rural surroundings found in this area.

The tunnel road itself is treelined and itself forms a small separate network of paths, distinct from the main roads. While not exclusive to these purposes, treelined roads are a typical feature for military roads and those used by the Kims. 

Location of the area's roads, secret tunnel, and the 'north-south road' which eventually merges with another road leading to the Mount Myohyang Palace.

The tunnel doesn't have a clearly defined exit point, but one may exist at 39°52'18.11"N 126°22'52.32"E, which is 0.7 km away. There is an apparent spoils pile indicative of tunneling work, but the available images are not clear enough to make a definitive identification. 

There is also no clear evidence of major excavation work using Landsat imagery going back to 1984. However, the small base next to the tunnel did exist in 1984, so either the tunnel was constructed prior to that year - when I don't have imagery - or it was built after but they took care to keep the site very clean, so land disturbances aren't especially obvious in the lower resolution imagery that Landsat provides. 

There is a main north-south road in the valley. The tunnel road connects to it and the possible tunnel exit would also connect to the main road. This road runs beneath Neultegi Mountain through a tunnel and continues on until it merges with another north-south road. This second road is protected and eventually goes under Myohyang-san, where it leads to a former mountain palace 12 km away. The tunnel under Myohyang-san was constructed ca. 1993.

The mountain palace was favored by Kim Il Sung and is rumored to be the place where he died. It was eventually demolished by Kim Jong Il.

This entire area, the valley, the treelined tunnel road, the second north-south road, and the area around Myohyang-san (Hyangsan) are all secured and traffic is regulated through the region. 

The region's security and the tunnel's connection with this closed-off road network is what makes this tunnel interesting. But unlike the tunnel through Neultegi, which is simply providing an efficient transportation route, the tunnel this post is talking about doesn't provide a better or safer route through the valley. In fact, if it does cut through the hill and exits on the other side, it would make the journey longer. From a strictly transportation viewpoint, the tunnel is pointless.

With all of this in mind, I think that the tunnel is either part of a larger tunnel network for the Kims as I have discussed before, or (particularly if it has an exit) that it could be a kind of emergency safe zone - a place where the Kim's motorcade could hide for a short period of time in the event of conflict or internal crisis until the surface roads became safe again.

Within 15 km of the tunnel are numerous military sites (including the HQ for the KPA IX Corps) and a series of other secured building complexes that are all located behind gates, roadblocks, and dead ends. It's within that wider network that this tunnel is located, and it is this complex interconnectivity that suggests this is no simple tunnel through a hill.

I would like to thank my current Patreon supporters: Amanda O., GreatPoppo, Joel Parish, John Pike, Kbechs87, Russ Johnson, Ryan Little, and ZS. 

--Jacob Bogle, 7/23/2022

Monday, June 6, 2022

The Largest Underground Sites in North Korea

Kim Jong-un visiting the Kanggye Tractor Plant. Image: Rodong Sinmun, June 2013.

There are over 2,500 underground sites in North Korea that have been publicly verified. They fall into five main categories: Hardened artillery sites, underground factories, underground storage facilities, underground air bases, and the underground facilities at missiles bases. There's also the large underground nuclear test site at Punggye-ri, several underground navy bases, and some others that are used for communications and emergency command sites, but those only make up a small number of the overall sites.

Other estimates place the number of underground facilities (UGF) as high as 14,000, but that would include everything from civilian bomb shelters to not-exactly-underground covered bunkers. And things like bomb shelters beneath apartment buildings isn't something that using commercial satellite imagery can easily work out.

So, of the ~2,500 UGFs that I can directly point out to you, a few stick out as being exceptionally large.

A note on estimating sizes. There are several fairly easy ways to estimate the size of an underground facility. The simplest of which is to look at the spoils dumped outside. Measuring the width and height of the rock piles can give you an idea of the volume being excavated. You can also consider the purpose (if known) of the UGF and what it might require in terms of size, you can look at the distances between entrances and service adits, and take into account the geology of the hill/mountain being tunneled into. 

Unfortunately, many North Korean UGFs don't have spoil piles to examine; the debris having been carried away to better hide the size of the facility. And looking at the distances between entrances only tells you that a tunnel exists, not necessarily a large complex with multiple floors and a warren of passageways.  

And, unlike underground airbases or artillery sites, not every UGF in the county has been assigned a purpose within open-source intelligence. That adds another layer of difficulty in estimating the size of a facility.

Therefore, this list comes with a few limitations. But whether or not this list contains the literal 14 largest UGFs (excluding missile bases) they are nonetheless among the largest in country. Some are rather astounding in size, at least to me, considering the state of North Korea's technology and the tools and skills they have available.

With that in mind, here are 14 of the largest underground facilities in North Korea.

Arms factories

The Kanggye General Tractor Plant (40°57'28.72"N 126°36'22.75"E) is the largest underground arms factory in North Korea. Also known as Factory No. 26, it was established soon after the Korean War after the original small-arms factory was split into three, and each part moved to different areas of the country.

The term "tractor" comes from Soviet nomenclature that typically denotes a military factory, with tractors rarely being made at "tractor" factories. Mortar ammunition, rifle ammunition, and self-propelled artillery ammunition are among the more common items produced at the factory, but they are also responsible for manufacturing short-range missiles.

Externally, the factory covers around 99 hectares. However, the factory has multiple underground entrances that provide access to the interior of a 1.8 km-long hill. While the exact size of the plant isn't known, the height of the hill would allow for multiple factory floors and several kilometers of tunnels.

It is estimated that the plant employs at least 20,000.

One of its biggest chapters occurred on Nov. 30, 1991, when an explosion rocked the factory.

Before and after images from Google Earth/Landsat showing a large area of land disturbance indicative of an explosion and clean-up efforts.

A mishandling of explosive material led to a small fire that eventually spread and caused a major explosion. Officials shut down communication in the area to stop news of the explosion from spreading and the disaster has never been publicly acknowledged. 

However, Landsat imagery from the time does show that something major happened at the factory.

Based on measurements of the imagery, the explosion destroyed an area nearly a kilometer wide and likely damaged every above ground building in the factory complex as well blew out windows for kilometers around. 

It has been alleged that the explosion killed around 1,000 people. If true, that would make it one of the deadliest defense industry-related disasters in history, perhaps only second to the 1917 Halifax Explosion which killed nearly 1,800.

It took 3-4 years for the site to be cleared and reconstructed, and, possibly as a legacy of the explosion, no new residential buildings have been constructed facing the factory, although the area does remain populated.

Panghyon Aircraft Factory (39°53'6.52"N 125°13'56.52"E)

First constructed in the 1960s, this factory used to be North Korea's only aircraft factory and it is still the primary factory that produces replacement parts for the country's fleet of aging MiGs and J-6 copies.

The factory is nearly 1.5 km long and is positioned around a hill. The primary underground entrance is ~14 meters wide and with 91 meters of overburden, a very large underground factory could exist, occupying upwards of 100,000 sq. meters.

It is believed that during the 1990s and early 2000s centrifuges for uranium enrichment were manufactured and stored at the factory, with as many as 300 centrifuges being held there. This provided a critical industrial component to North Korea's nuclear infrastructure. There is no indication that the factory is still produces centrifuges today. 

Panghyon has also been the site of ballistic missile launches includingHwasong-14 ICBM launched on July 4, 2017.

Tonghungsan Machine Plant (39°57'11.97"N 127°32'48.35"E)

Tonghungsan is a large factory that is suspected of producing missile components and parts for mobile launchers. It is split into two main sections, above ground production facilities and the underground complex.

The above ground part of the factory has been undergoing a complete reconstruction since 2016 and now includes 19 production-related buildings, 11 administrative and support buildings, and the reconstruction also involved building 31 residential buildings and several other structures such as schools and cultural/communal sites.

The construction also extended to the entrance and security buildings that lead to the underground entrance. The primary entrance has two portals that are 60 meters apart. A service adit (portal) is visible 140 meters north and piles of excavation spoils can also be found 400 meters from the main entrance, and another pile is 820 meters away. Yet another adit is also located on the other side of the mountain, 1.3 km away from the entrance at 39°57'45.31"N 127°32'13.21"E.

Simply connecting these visible parts of the UGF suggests that there could be at least 291,000 sq. m. of underground space. If there are multiple levels, that could reach upwards of 400,000 sq. m. given the area's geology. Of course, large underground facilities aren't massive single caverns. They have galleries (halls), support structures, and may need to avoid weak spots in the rock, so the real size of usable space will be less than 400,000 sq. m., but it could still be the equivalent in size to an automobile factory or the Louvre Museum, all beneath a mountain.

Major Underground Airbases

Twenty-one North Korean airbases have underground facilities, but the following six bases represent the largest in terms of the underground tunnel length and the amount of possible internal space.

Koksan AB (38°40'34.89"N 126°35'40.69"E)

Koksan AB consists of a single 2,496-meter-long runway and is home to the 86th Air Regiment and stations twenty-four MiG-21 fighter jets at the base. 

The underground facility employs two main entrances for jets to enter beneath a mountain that rises 120 meters above the facility. The entrances are ~185 meters apart and there is also a service access tunnel that's ~600 meters to the south of the main entrance. This suggests that the Koksan UGF could have 96,000 sq. m. of underground space.

Nuchon AB (38°13'52.09"N 126° 7'43.57"E)

Nuchon consists of a single 2,495-meter-long runway and is home to the 32nd Air Regiment (fighter-bomber) and is home to several J-5/MiG-17, MiG-21PFM, Mi-2 aircraft.

The tunnel connecting the two underground entrances is 575 meters long. At a minimum, the UGF covers 18,450 sq. m. but the hill above contains enough overburden to support a theoretical UGF up to three times that size if there are galleries that branch off the main tunnel.

Onchon AB (38°53'13.32"N 125°16'29.39"E)

Onchon is unique in that it has the only fully functional underground runway in the country. The base's primary runway is 4 km to the west.

Onchon is home to the 36th Air Regiment (fighter). At least 36 aircraft are stationed at the base.

The underground complex consists of an underground runway, with 700 meters of it going underground, and two underground entrances used to bring aircraft inside of repair and storage facilities. The two entrances are 280 meters apart.

Connecting the entry tunnels and underground runway area together would yield a UGF of 51,800 sq. m. If the internal layout is more complex with extra galleries, the theoretical maximum size grows to roughly 160,000 sq. m. 

Pukchang AB (39°30'44.60"N 125°57'28.76"E)

Pukchang is home to the 58th Air Regiment (fighter) and 60th Air Regiment (bomber) and has MiG-23MLs and MiG-21Bis stationed at the base; with upwards of 60 aircraft being stationed here at any given time.

Pukchang has three underground entrances that are spread out by 400 meters. I suspect that the internal layout of the UGF is fairly simple and does not greatly expand into the hill any more than what's needed to connect the three tunnels and provide some extra storage/maintenance space. This gives an underground area of 11,000 sq. m. at a minimum but likely no more than 16,000 sq. m.

Taetan AB (38° 7'3.70"N 125°13'21.97"E)

Taetan Airbase is home to the 4th Air Regiment (fighter) and has two runways. One is 2,810 meters long and the other is 2,490 meters. The UGF entrances are ~1.3 km away from the runways.

The two underground entrances are ~540 meters apart. Reviewing the area, I think the UGF consists of a single large rectangular structure (built from the tunnels and 'inward' toward the south) with no side galleries or other structures beneath the hill. A straight-line tunnel directly connected to the entrances yields and area of 19,000 sq. m. The surmised rectangular UGF would occupy 59,000 sq. m. There is no visible evidence of access adits or spoils from excavations further into the hill that would suggest a substantially larger facility.

And lastly, Kang'da-ri AB (39° 5'48.78"N 127°24'51.67"E)

Like Onchon, Kang'da-ri also has an underground runway, but the facility doesn't appear to be actively used by aircraft, leaving Onchon as the only active underground runway in North Korea.

The Kang'da-ri complex consists of a primary runway on the left bank of a river and an underground runway. The primary runway was modernized in 2009/2010 but has since been abandoned and left to deteriorate each time the river floods. 

The underground history of Kang'da-ri goes back to 1998 when the initial excavations into the small mountain began. Work has carried on in fits and starts, with the most recent work appearing to have stopped in 2018.

The paved portion of underground runway is 1,748 meters, with ~750 meters of that actually being underground. 

It has been claimed that the base is part of the 2nd Air Combat Division, but no aircraft can be seen in any of the images available on Google Earth. Additionally, Joshua Stanton has said that the runway is too small for fighter aircraft. 

The true purpose of the base is unknown, but part of North Korea's chemical weapons program is said to be based at Anbyon, a town just 11 km away. However, there are few military facilities at Anbyon that would be suitable for chemical weapons storage, but the underground Kang'da-ri runway is protected by large blast doors and it cannot be directly accessed by any major highway - adding to the site's security. So I think the base is a candidate location for weapons' storage (chemical or otherwise), particularly since the government has seemingly taken 24 years to build an incomplete "airbase".

Unidentified large UGFs

Hagap UGF (40° 4'54.23"N 126°11'22.74"E)

Hagap has been written about extensively (including on this site here & here), but it is in this section because we still don't know what the place is actually supposed to be. The two prevailing theories are that it's either an underground uranium enrichment plant or that it is part of the national archives.

The enrichment theory was put forward the moment Hagap became publicly known about in 1998. Given the construction of the Kangson enrichment plant near Pyongyang, and that Hagap still has not been completed, it would make its existence redundant (and very expensive) as an enrichment site. However, it could play any number of other roles within North Korea's nuclear program.

The other theory put forward is that it is meant to ultimately become an archives facility capable of protecting the most important documents and artifacts from even a nuclear blast.

After several years of apparently being dormant, new construction began at Hagap in 2011/2012 with a new underground entrance being excavated and the spoils were used to lay the foundation for an access road. This work was carried out methodically until in 2015/16 the pace of construction was sped up and new work could be seen throughout the eastern side of the complex. 

This construction coincided with underground work being carried out at the International Friendship Exhibition located a short 8 km away. The IFE is where North Korea houses the countless gifts, medals, and awards given to the country's leaders over the decades and is used in propaganda as proof of the greatness of the Kim family. 

Concurrent construction at both sites could merely be coincidence, but I think it might add a little weight to the theory that Hagap is actually meant to be part of a highly secured national archives, perhaps holding the true histories of Kims and government that are too dangerous to be accessed by anyone but the most devout followers of Juche or that it will hold the foundational documents and artifacts of the country to protect them from war or natural disaster.

Based on the locations of the underground entrances, there is a primary tunnel capable of handling vehicle traffic that runs for ~500 meters. The facility very likely also extends within the mountain for another 400-500 meters.

Sonjesan UGF (39°18'46.95"N 125°55'33.74"E)

Sonjesan is an interesting site. It is located in a random hill halfway between Pyongsong and Sonchon. It has no obvious industrial infrastructure or particularly tight security. At the same time, the roads leading to the UGF also go through multiple nearby military facilities, and it has four entrances.

The main entrance is at 39°18'46.95"N 125°55'33.74"E but the above image is centered on the two rear entrances at 39°18'35.52"N 125°55'50.47"E because they show up the clearest in the available imagery.

Connecting the four entrances into a simple rectangle yields a potential area of 95,700 sq. m., that's over a million square feet. Sonjesan also has visible spoils piles and examining those shows that at least 100,000 cubic meters of material has been excavated out of the hill. 

In 2020, the original buildings at the main entrance were demolished and new ones built. Another point of excavation that is almost certainly connected to the primary UGF was also opened in 2016, with the spoils pile growing each year into 2021. The pile contains approximately 6,300 cubic meters of material.

A nearby sixth site was constructed in 2017/18 at 39°18'14.84"N 125°55'40.66"E, along with a new military base, but I'm not sure if this tunnel connects to the main facility or if it's simply its own small UGF. 

Taedonggang UGF (39°10'25.07"N 125°56'43.60"E)

Located by the Taedong River, near the Kangdong Leadership Residence, its four entrances are spread out along nearly 300 meters and the site could also be connected to a large artillery position 520 meters away that itself has an underground component. 

The four entrances are grouped into two groups and I don't think they're connected to each other. So the actual underground facility may not technically be among the largest because of this, but the overall complex itself it rather large. The particular layout of the UGFs is also uncommon.

The roads leading to the entrances are also quite wide and would allow access to vehicles that have wide turning radii such as missile launchers or large artillery systems. 

Interestingly, at the end of the base is a large overhead crane, such as one might see at a containership port or factory. New buildings were added at the crane site in 2019. The presence of the crane could suggest that the base is, in fact, used more for storage and maintenance (perhaps even of industrial equipment) than as an active missile or artillery base. 


Abandoned/Unsused UGFs

The Kyongje-dong Bunkers 38°34'36.46"N 125°56'8.15"E

The bunker complex at Kyongje-dong are one of the more enigmatic facilities in North Korea. The two bunkers are much too large to have been purpose-built for missile launchers, they don't extend deep enough into the hillside to be a typical storage facility, and they aren't part of a factory or other industrial infrastructure. 

Joseph Bermudez and Victor Cha over at the Center for Strategic and International Studies helped to shed a good deal of light on the bunkers. It is perhaps the most detailed open-source report on them.

The initial preparations for construction took place in the 1980s, but primary excavation work began in 1993. The facility was completed in 1998.

The two bunkers have entrances 40-meters wide, and they each have a large concrete pad in front that measures 60 by 40 meters. The entrances are protected by blast doors, and the earth-covered bunkers themselves are approximately 60 meters long.

The CSIS report goes on to say that the facility is most likely a reserve site that would serve as a forward operating base for MD-500 helicopters in the event of war, allowing special forces operations to penetrate much further into South Korean territory than other existing heliports would allow.

Hamhung abandoned UGF - 39°59'50.27"N 127°42'52.09"E

This site is 17.5 km northeast of downtown Hamhung. When I first came across it, I thought it was a mine, but a closer inspection of the main area reveals what is apparently a large tunnel protected by what can only be described as blast doors.

Looking at historical imagery on Google Earth shows that work began at the site in 1996 and work was ongoing in 2008. The UGF sits at the end of a valley, with the rest of the valley filled with numerous support buildings spanning 1.7 km. But by the early 2010s, work was halted. Nearly all of the buildings were then removed in two phases, one in 2016 and the other in 2021.

The primary tunnel face is ~45 meters wide and there is what looks to be a large metal frame to hold protective doors. A second entrance was created but has since been closed, possibly as the result of rock collapsed. 

The crane that was used to move materials into dump trucks has been kept in place.

It's still possible that the site used to be a mine, but if so, its design is unique in North Korea. If it was meant to be an underground facility, I think geologic problems developed as they dug deeper into the mountain, perhaps causing severe leaks or internal collapses. This wouldn't be the first time a UGF in the country had to be abandoned due to collapse. A coastal defense battery had a large cave-in back in 2016.

I also want to add an honorable mention to the network of tunnels that protect the Kim family. These road and rail tunnels connect various palaces and military command centers together, enabling the Kims to move around the country securely during a time of war or to evacuate one place and get to another. Most of this network is still hidden but there are some known/suspected parts of it that rise to the surface and can be seen by all.

One tunnel is particularly well known. It is a two-lane paved road (39° 9'50.83"N 125°59'26.98"E) that dives beneath the Taedong River near the Kangdong Palace and then reemerges a kilometer away. It is surmised that there is another tunnel that pulls off from the main one and connects to other elite areas in the region.

Another part of the network uses the country's railways. The Obong-ri Elite Train Station (40°18'18.13"N 125°12'18.72"E) is positioned in a mountainous region north of Kusong. The entire complex encompasses roughly 17 sq. km and contains two train stations, housing for personnel, various support structures and it has two rail lines that go into a hill and disappear. It is not known if this is simply an underground train repair center or if the lines continue underground and could carry Kim Jong-un many kilometers away on his armored train without anyone knowing.

I would like to thank my current Patreon supporters: Amanda O., GreatPoppo, Joel Parish, John Pike, Kbechs87, Russ Johnson, and ZS. 

--Jacob Bogle, 6/5/2022

Wednesday, May 25, 2022

Phishing for AccessDPRK

Every so often NK News will report on mass attacks against North Korea researchers by North Korean agents or pro-Pyongyang groups.

From hacking attempts to phishing, I have been the target of half a dozen of these attacks and possibly more that I'm not aware of.

One of the common methods used is to impersonate a real journalist from a real news agency, and they will send you an email with a list of questions for their "upcoming article". If you don't notice the attempt for what it is (like by observing the email being used is from a free account and not a business one) and you send them your replies, they'll turn around and send you a password protected Word document saying they have some extra questions or want your input on the final draft prior to publication.

If you download the file and try to open it, it can unleash a range of attacks against your computer or phone, or download some malicious code that just sits there, quietly sending the attacker all of your activity.

The latest attempt to scam/hack/infect came in the form of an interview request. But you know what? Instead of just ignoring the situation, the faux questions they asked were actually kind of interesting and are on a topic many have been considering lately - what impact the war in Ukraine might have on North Korea's behavior.

So just for fun, here's what I would have said in the event I was actually being asked these questions by a legitimate reporter.

Question 1: Some analysts argue that Russia’s invasion of Ukraine may make North Korea much more reluctant to give up nuclear weapons, given that Ukraine has now been invaded by Russia after it abandoned its nuclear arsenal in exchange for security guarantees under the Budapest Memorandum. This certainly looks similar to an agreement made between Trump and Kim Jong Un in Singapore in 2018. What do you think about this kind of argument?

Reply 1: North Korea's nuclear program dates back to soon after the Korean War. It has been an integral part of both the military and political landscape for decades. And the leadership already learned the lessons taught by the deaths of Saddam Hussein and Muammar Gaddafi, which is that giving up your nuclear program is no blanket guarantee of regime survival.  

So, I don't think the invasion of Ukraine will have much of a direct influence on North Korea's thinking regarding survivability as they already strongly doubt the West's sincerity. 

A major flaw with the Singapore agreement is that it largely repeated what was agreed to in previous agreements going back to the first Inter-Korean summit in 2000, and it didn't provide a framework or guidance on how to actually accomplish the goals it set forth. In other words, unlike the Budapest Memorandum which was a legally binding agreement as part of Ukraine's accession to the Nonproliferation Treaty, the Singapore agreement was symbolic and aspirational; something either side could easily ignore.

Question 2: While the Biden administration is concentrated on the evolving circumstances surrounding Ukraine, possibly lowering its guard in the Asia-Pacific region, North Korea may try to develop new type of weapons including ICBMs or carry out nuclear tests. What do you think about North Korea’s future developments?

Reply 2: One common misconception about North Korea and the Kim regime is that they're mysterious and irrational. To the contrary, they can be quite transparent about their goals if one pays attention. Kim Jong-un laid out a series of military goals at the Eighth Party Congress in 2021 that included everything from developing hypersonic missiles to tactical nuclear warheads and even launching a military reconnaissance satellite. 

North Korea also never closed the Punggye-ri Nuclear Test Site, they only destroyed the tunnel entrances which could quickly be repaired if needed. Low-level activity has been seen throughout the wider Punggye-ri complex every year since its "closure" in 2018, and the government has recently begun the process of repairing the tunnel entrances and are likely preparing for another nuclear test. Additionally, Kim Jong-un said that he no longer felt bound by the self-imposed nuclear testing moratorium, and in January of this year, North Korea announced that it would consider restarting all of their suspended activities. 

It seems clear that North Korea has been conducting covert weapons development and production throughout the last few years, despite claiming they had stopped, which enabled them to test hypersonic glide vehicles and rail-based ballistic missiles. And, clearly, the government has been planning to conduct more tests and produce new weapons, as Kim Jong-un explicitly laid out.

The issue isn't necessarily that the Biden Administration hasn't been focused enough on North Korea, but that North Korea has never liked feeling ignored. They have a history of missile testing and even engaging in direct attacks against South Korea whenever they feel the international community's gaze has fallen elsewhere (in this case, Ukraine). So it's certainly likely that a new missile test or even a nuclear test could be conducted soon. This risk is also enhanced because of the recent elections in South Korea and Biden's visit to Seoul and to Japan. During events like this, North Korea has a tendency of provocative behavior.

Question 3: Do you think North Korea believes that Biden is already a “lame duck” and sees this as a good chance to concentrate on developing new weapons?

Reply 3: The Biden administration has appeared to be slow in appointing the relevant special envoys and ambassadors to the region, and much of the United States' government has been preoccupied with domestic problems. The economic fallout from COVID-19 such as supply chain issues and inflation has indeed damaged Biden's prospects for the US mid-term elections and for his own reelection chances in 2024, so it is possible that Pyongyang is simply trying to ride out the clock and wait until the US has new leadership.

At the same time, North Korea hasn't exactly been dormant. They've conducted at least 17 missile tests in just the last 5 months and are repairing the facilities at Punggye-ri. Given the dramatic improvements made to their nuclear and missile programs over the last several years, it is my feeling that Kim cares less today than ever about who sits in the White House and isn't overly concerned with whether or not Biden would be capable of meaningful engagement. 

Considering that in April Kim Jong-un announced the end of North Korea's erstwhile "no first-use" policy and threatened preemptive nuclear strikes, it paints a story that Pyongyang is becoming bolder and feels more secure to do what they want (even if the actual risk of a preemptive strike is vanishingly low).

Question 4: Do you expect China will tolerate North Korea’s spate of ballistic missile launches and possible ICBM or nuclear tests? Do you think North Korea can or will maintain stable and amicable relations with China? Does Russia not afford to care about North Korea?

Reply 4: The short answer is, China has tolerated North Korea's actions so far, so why wouldn't that continue? Unless North Korea launches a full-scale war, nuclear or conventional, China will support North Korea. This isn't out of a sense of socialist brotherhood, but because it is in China's own interest to maintain the North Korean state.

China is directly responsible for North Korea's ability to evade sanctions and has been willing to supply the country with extra oil, luxury goods, and numerous other items that are banned by international sanctions. 

On occasion, it has tightened the enforcement of sanctions and admonished North Korea after particularly major events such as the 2017 nuclear test, but there is little to suggest Beijing would alter or reverse its decade's old policy toward Pyongyang absent a very serious incident - which ICBM launches apparently no longer qualify as. The rise in COVID cases in North Korea also makes China's continued support all the more necessary to avoid any potential destabilization of the country.

As for Russia, Putin and Kim have tried to improve relations and that has born some fruit including $10 billion in debt forgiveness, a 2015 agreement to construct a road crossing, and the expansion of the current railway crossing located in Rason. However, trade has remained minimal, and it would take more investments and time to further develop trade between the two countries.

In the wake of the war in Ukraine, it's likely that Russia and North Korea will seek to develop closer relations (North Korea was one of the five nations who opposed the UN resolution against the war) but I wouldn't predict any substantial shifts in policy. 

Along with China, Russia has also routinely blocked efforts to pass UN condemnations of missile tests and to impose new sanctions. And like China, Russia would rather have an anti-West nuclear-armed state on its border, than one that is closer to the West (which would be the result if North Korea began to cooperate).


I've publicly released tens of thousands of map locations and have written over a thousand pages combined worth of material on this blog, NK News, 38 North, Asia Times, National Interest, and others. If you want to know what it is I know so desperately, join my Patreon like everyone else and get access to exclusive information you won't find on the AccessDPRK blog.

Speaking of Patreon, I would like to thank my current Patreon supporters: Amanda O., GreatPoppo, Joel Parish, John Pike, Kbechs87, and Russ Johnson. 

--Jacob Bogle, 5/24/2022