Mystery at Pyongyang Security Ministry

In 2020 the People's Security Department (aka Ministry of People's Security) was renamed the Ministry of Social Security. The MSS oversees a number of functions including police, prisons, assists in securing the distribution of food, and aides other security agencies.

It is one of the three "pillars" of DPRK state security. The other two are the military and the Ministry of State Security.

One of their facilities, according to the 38 North Digital Atlas, is this complex on the western outskirts of Pyongyang. Its coordinates are 39° 3'10.50"N 125°40'14.21"E. Landsat/Copernicus imagery suggests this facility was built ca. 1989-1992 but the satellite resolution is low enough as to make a fully certain date range difficult.

In recent years, an underground complex has been constructed. Underground facilities (UGF) are not rare in North Korea, but this one consists of a "cut and cover" tunnel - not one that is excavated into a hill but where a trench is dug, the tunnel structure built, and then the site is covered over to hide it. Identifiable examples of cut and cover tunnels are indeed rare in the country.

The exact purpose of this tunnel/underground facility is a bit of a mystery, but considering its location, I feel that detailing its ongoing construction history is important.

General outline of the complex.

The two sections of the complex are joined by a tunnel that runs beneath the central hill dividing the site. The tunnel is approximately 188 meters in length.

The tunnel allows vehicles quick access to each side of the complex without having to go around the hill. The facility has undergone many changes over the years, but this tunnel has existed since at least 2000.

At the very rear of the complex is another underground site. Whether or not it is directly connected to the Ministry complex isn't known but its proximity is interesting.

A trench has existed at the left-side facility since at least the year 2000 and implies that plans for this new underground structure have been around for a long time.

The trench excavation runs about 205 meters long and averages 12 meters wide.

Little else changed at the site until 2013 when several temporary buildings were constructed near the trench, and minor work at the upper end of the trench can also be seen. (Clearer images of this work come from 2014.)

Image showing construction activity in November 2013.

By September 2014, the upper portion of the tunnel is taking shape and a new building had been constructed at the site they were leveling off in 2013.

In 2014 other changes become visible including the addition of multiple permanent buildings (some were still under construction at this time).

By this time, it's clear that a tunnel had been excavated, the sides of the trench had been shored up, and the debris pile shows activity. It isn't known if this tunnel goes into the central hill or connects to the road tunnel between the two sections, but if you draw a straight line following the new walls of the trench, it does intersect with the existing road tunnel.

This at least theoretically gives the possibility that the entire central hill is actually a large underground facility that now has three points of access: the original road tunnel, the new tunnel under construction, and the older rear UGF. This part is merely speculation but the possibility of a large hidden facility is very interesting, as we know that numerous underground facilities exist in North Korea including some that are used in training security forces to hide their clandestine activities.

By April 2017, a concrete structure (or "box") can be seen inside the trench. At this stage, it is approximately 40 meters long and 5-6 meters wide. Additional work around the area to prepare for more construction has also taken place.

On the image dated October 26, 2017, it becomes clear that the concrete section from April was just one small part of a larger concrete tunnel structure that is now 155 meters long and about 10 meters wide.

This type of structure is similar to long military "drive thru" bunkers that exist throughout the country (at least 400 exist at last count). One such example is this bunker, also in Pyongyang, that is similarly divided into two segments and is 10-12 meters wide. It is approximately 190 meters long. These structures are typically used to house and protect various vehicles.

However, these other drive thru bunkers are usually seen as part of military bases and never as part of building construction, making this Ministry structure unique as far as I am aware.

By April 2018, the tunnel had been covered and the area leveled off. The foundation of a new building had also been dug at the north end of the site.

Fast forward to the end of 2019 and the new building has been completed and an entrance site to the tunnel was nearing completion (final touches, landscaping, etc.) By November, another foundation can be seen. The new foundation is in the middle of the construction site and sits on top of the tunnel.

Based on the most recent Google Earth image, there is vehicle traffic going in and out of the tunnel. The square foundation has also had some additional work.

On the above March 13, 2020 image, you can see a driveway leading into the new foundation. The angle doesn't allow for this to be a second entrance into the main tunnel. The whole area has been raised above the tunnel, however, allowing for a low/shallow basement to exist at the new building site. This most likely where the driveway is going.

More recent satellite imagery (that I am not free to share publicly) shows that construction at the site is slow but ongoing. Unfortunately, it doesn't provide further clues to the site's purpose.

Lastly...

While not associated with this site at the Security Ministry, there is another underground construction that likewise began in 2017 and consists of a main tunnel structure. Its coordinates are 39°11'38.26"N 125°45'14.04"E, or 1.8 km north of the Kim Jong Il People's Security University in northern Pyongyang. The tunnel entrance is 12-13 meters wide and it has no apparent exit point.

I would like to thank my current Patreon supporters: Amanda O., Anders O., GreatPoppo, Kbechs87, Planefag, Russ Johnson, and Travis Murdock.

--Jacob Bogle 7/11/2020
AccessDPRK.com
JacobBogle.com
Facebook.com/accessdprk
Twitter.com/JacobBogle

Missile Bases & Major Underground Sites

North Korea is perhaps the most militarized country in history. As a country roughly the size of the US state of Pennsylvania, it has literally thousands of distinct military sites: air defense, training bases, coastal artillery batteries, airbases, missile sites, tunnels, and much more. Because of the country's nuclear program, their missile bases receive a lot of attention. However, there is still a lot that is unknown about these sites, in part, because North Korea has only officially acknowledged a handful of them (and often just in vague terms).

The satellite facilities at Sohae, Tonghae and the Chiha-ri missile base are fairly well known, but the good folks over at Beyond Parallel (part of the Center for Strategic International Studies) estimate there may be as many as 20 undeclared ballistic missile bases and related support facilities. The 2017 release of "Phase II" of the AccessDPRK mapping project listed over 9,500 military points of interest, and since then, I have begun work on the next part of the map which now includes an additional 1,500 military sites. Using this unpublished version, I decided to see what likely missile bases and large underground facilities exist in the country. (These stand-alone underground facilities are something Beyond Parallel isn't looking at.)

After going through every identified military base, tunnel, underground facility (UGF), known and suspected missile base, and other sites, I was able to locate 19 known and possible ballistic missile bases, the two satellite launch stations, and 39 large UGFs that are separate from the missile bases.


North Korea considered the creation of a ballistic missile program soon after the Korean War and it became an official goal as early as 1965, with Kim Il Sung saying the country needed to have rockets that could fire as far as Japan. From then until the early 1980s, the regime laid the foundations of the program including the acquisition of Soviet and Egyptian technology. In 1984 they were able to test their first indigenously produced missile which was a variation of the SCUD-B.

The height of their missile program came with the first internationally verified successful orbital insertion of a satellite into space in 2012, the Kwangmyŏngsŏng-3 Unit 2, followed by the 2017 test of the Hwasong-15 missile which can reach nearly all of the United States.

The vast size of North Korea's missile program infrastructure (dozens of locations in a country the size of Pennsylvania) helps to ensure that they can continue to carry out attacks if one or several bases are destroyed during a war. It also makes it all the more difficult for Western powers to keep track of the movement of weapons and equipment.

North Korea's ballistic missiles and ranges. Image from the Center for Strategic International Studies. 

By 2017 the country was thought to have around 900 short-range missiles, though that figure may have grown to 1,000+ with the apparent development of a North Korea-produced clone of the Russian Iskander missile. (As well as from the continued production of known missile systems.)

• Short-range missile are typically defined as having a range of 1,000 km (620 miles) or less. Examples include the KN-02, Hwasong-6, and the aforementioned Iskander clone.
• Medium-range missiles have a range of 1,000-3,000 km (620-1,860 mi). Examples include the Rodong-1 and Pukkusong-2 (KN-15). North Korea likely has 500 or fewer of these missiles.
• Intermediate-range missiles can reach 3,000-5,500 km (1,864-3,418 mi). An example is the Hwasong-12. There are likely fewer than 250 IRMBs.
• ICMBs (intercontinental ballistic missiles) have a range exceeding 5,500 km (3,400 mi). North Korea's Hwasong-15 is their latest developed ICBM. There are probably fewer than 75 operational missiles in this category.

The country's missile bases are divided into three main "belts". They are, with increasing distance away from the DMZ the, "tactical belt", "operational belt", and "strategic belt". The different belts reflect the types of missiles deployed at each base, with the strategic belt holding long-range missiles (this includes the submarine base at Mayang) and the tactical belt being the site of shorter-range missiles aimed at the DMZ, Seoul, and other important South Korean sites.

Pyongyang's missile program is under the control of the Korean People's Army (KPA) Strategic Forces and the construction of the bases is done by KPA Unit No. 583 (the Military Construction Bureau). Substantial construction began for many of the bases in the late 1980s to mid-1990s, and construction at all sites had either already began or was scaled up by the 2000s. Several ballistic missile bases, such as Chiha-ri and Yusang-ni, have had upgrades since Kim Jong Un came to power.

A note on naming. Unless a name has been given in an official North Korean or US-ROK alliance intelligence source, all of the locations talked about in this article are otherwise named for the nearest populated place as listed by OpenStreetMap. A lack of standard naming has led to confusion for years, but that's one thing this article seeks to remedy. And, instead of simply saying "a base in Chagang Province" or "by Kimchon-ni" (when there are multiple villages with the same name), this article will list the base's exact coordinates.

These twenty-one main facilities occupy approx. 362 square kilometers of territory. Despite my best efforts, I wasn't able to positively identify the To'gol base (allegedly in Pyongsan County) or the Kittaeryong base (in Anbyon County).

Within the "tactical belt" are:

1. Chiha-ri - Coordinates are: 38°36'10.63"N 126°44'12.20"E
2. Kal-gol - Coordinates are: 38°40'3.15"N 126°44'49.97"E
3. Kumchon-ni - Coordinates are: 38°57'54.14"N 127°36'8.48"E. Kumchon-ni has been detailed by Beyond Parallel.
4. Sakkanmol - Coordinates are: 38°34'59.81"N 126° 6'29.91"E. Sakkanmol has been detailed by Beyond Parallel.
5. Sing'ye - Coordinates are: 38°38'24.31"N 126°40'48.26"E. Sing'ye is one of the smallest missile bases in the country. It may also be the source name for the Hwansong-class of missiles as a nearby village is named Hwasong, and the base was constructed early on.
6. Suthae-ri - Coordinates are: 38°22'51.67"N 127°29'0.55"E. Suthae-ri is a possible base and hasn't been mentioned in any media that I could find. At less than 10 km from South Korean territory, it would be the closest ballistic missile base to the DMZ. The base doesn't have the "drive thru" bunkers that many other known bases have, but it does have a large and expanding underground facility and several bunkers of other types.

Chiha-ri, Kal-gol, and Sing'ye are all within 5 km of each other, which would lead me to believe that they are connected in some way; perhaps in mutual-supporting roles.

Within the "operational belt" are:

1. Hodo - Coordinates are: 39°24'30.31"N 127°32'5.63"E. The Hodo base is very small and is more for testing missiles than as an operating base during conflict. Hodo seems to have replaced the beaches at Wonsan for testing sort-range missiles, as the site at Wonsan is now a cluster of hotels.
2. Hwajil-li - Coordinates are: 39°11'52.58"N 125°23'56.93"E. Hwajil-li is listed by the Nuclear Threat Initiative as a missile base that was constructed in the 1980s. Current satellite imagery doesn't show anything that would suggest the site is currently used as a missile base. A basic air defense battery and associated facilities is all that exists today.
3. Ongpyong - Coordinates are: 39°19'33.69"N 127°19'50.68"E. It is a smaller base and its facilities may be dispersed throughout a larger area. There are ongoing questions about the site's true purpose, and it may not be a ballistic missile base but rather a support facility for region air defense sites. 

4. Sil-li - Coordinates are: 39°10'49.68"N 125°39'48.84"E. Sil-li is located next to the Pyongyang-Sunan International Airport and is a "ballistic missile support facility", which is not the same as an "operational ballistic missile base". It was constructed from 2016-2020, and has been detailed by Beyond Parallel. 
5. Singsong-ri - Coordinates are: 39°21'32.23"N 125°45'49.57"E. Singsong-ri is a possible base. Like Suthae-ri, it doesn't fit the design of a lot of other known bases, but it does have three underground entrances which run deep into a mountain. If it is indeed a base, it's likely used to store missiles and equipment.
6. Yusang-ni - Coordinates are: 39°26'51.58"N 126°15'30.33"E. Yusang-ni has been detailed by Beyond Parallel.

On average, the land area used by these bases is smaller than bases in the other two belts.

Within the "strategic belt" are:
This belt includes the country's two satellite launching stations as they have played a role in the development of ballistic missile technology and could be used as launching sites.

1. Hoejung-ni - Coordinates are: 41°22'21.64"N 126°54'46.14"E. Hoejung-ni is one of the newest missile bases to be constructed. It is only a few kilometers from the base at Yeongjo-ri
2. Kusong-ri (alleged) - Coordinates are: 39°59'51.22"N 124°34'16.80"E. According to Jane's/IHS, this surface-to-air missile base may also house some Nodong missiles; however, this has never been conclusively demonstrated and it is likely only an air defense base based on the most recent satellite imagery.
3. Riman-ri (Yongnim) - It is the largest base by area and covers approx. 72 sq. km. Coordinates are: 40°29'2.94"N 126°30'1.65"E
4. Sangnam-ri - Coordinates are: 40°50'20.20"N 128°32'35.82"E. Sangnam-ri has been detailed by Beyond Parallel.
5. Sinpo-Mayang - Coordinates are: 39°59'42.09"N 128°11'43.98"E. Sinpo houses part of a large submarine base (the other half being on Mayang Island) and has a missile test stand. The base is where North Korea is developing their submarine launched ballistic missiles. The base is not an operational ballistic missile base where missiles would be fired from, but I have included it for its role in the development of SLBMs and the fact that any future SLBM-capable submarines would be based at Sinpo-Mayang.
6. Sino-ri - Coordinates are: 39°38'57.32"N 125°21'36.37"E. Sino-ri has been detailed by Beyond Parallel.
7. Sohae Satellite Launch Center - Coordinates are: 39°40'6.88"N 124°42'30.44"E
8. Taegwan - Coordinates are: 40°18'34.10"N 125°16'17.02"E
9. Tonghae Satellite Launch Center - Coordinates are: 40°52'13.09"N 129°38'34.10"E. My discovery of a missile test stand being constructed at the site was the basis of my very first #AccessDPRK post back in 2013.
10. Yeongjo-ri - Coordinates are: 41°19'44.56"N 127° 5'35.38"E. Once considered a nuclear site, Yeongjo-ri is actually a missile base.

The next area I want to explore is the collection of large underground facilities (UGFs).

As mentioned earlier, these UGFs are not part of any obvious missile base. Underground sites abound in North Korea and serve as active and reserve storage sites for weapons, equipment, food, and other supplies, and they allow for artillery to be fired and then rolled back into the tunnel for protection against counter strike. There has been a lot of speculation about the number of tunnels and underground sites within the country with some estimates going as high as 100,000. Based on the work for AccessDPRK, the real figure is much closer to 1,000 sites (some may have multiple entrances, but they're part of a single facility). Most of them are small and some are used as underground factories. But there are a few dozen (39 to be exact) which are much larger than any of the others (excluding underground industrial sites).

Some of them are placed at military bases and consist of a single complex while others exist as clusters, especially in Pyongyang.

There are four UGFs in Chagang Province.
1. Oil-rodongjagu UGF - 40°59'53.82"N 126°46'51.12"E
2. Janghang UGF - 40°57'32.66"N 126°41'9.98"E
3. Kanggye-Puji UGF - 40°53'12.75"N 126°38'4.45"E
4. Jonchon UGF - 40°32'49.08"N 126°19'48.21"E. This facility is across from the Riman-ri (Yongnim) missile base and so may be connected to it in some way.

There are three UGFs in S. Hamgyong Province.
1. Toksan UGF - 40° 1'52.84"N 127°35'48.28"E
2. Sinphung UGF - 39°58'7.64"N 127°50'17.89"E
3. Songhung UGF - 39°22'54.97"N 127°10'43.71"E

There are five UGFs in Kangwon Province.
1. Chongdu-ri UGF - 38°22'2.71"N 128° 2'20.19"E
2. Wondong-ri UGF - 38°24'51.14"N 127°41'59.76"E
3. Konsol-li UGF - 38°29'30.47"N 127° 0'7.53"E. The UGF here is part of a new military base that was constructed in 2016-2017.
4. Jisang-ri UGF - 38°34'44.13"N 126°44'5.59"E
5. Kubong-ri UGF - 38°37'44.89"N 126°43'15.55"E

There are four UGFs in N. Hwanghae Province.
1. Phyongwon UGF - 38°46'42.16"N 126°27'47.77"E. This has a very large UGF and might actually be part of their missile infrastructure.
2. Taephyong UGF - 38°26'5.60"N 126°20'37.53"E
3. Misan-ri (Kyongje-dong) - 38°34'41.50"N 125°56'6.04"E. This is a set of two enormous bunkers that would serve as a hardened helicopter base during conflict.
4. Okhyon - 38°22'4.16"N 125°44'22.81"E

There are 23 UGFs in Pyongyang. Eleven of them are in three clusters. Each cluster will only get one set of coordinates.
1. Pyongyang Group 1 - 39° 5'58.09"N 125°49'48.07"E. There are three large tunnels/entrances that spread out in an east-west line approx. 1 km long.
2. Pyongyang Group 2 - 39°10'11.96"N 125°51'28.16"E. This is a set of five large tunnels that are along a valley between two sets of hills. From the coordinate given, a rectangle is formed by a line running 1.4 km west to east and then from that point, north to south for ~0.5 km.
3. Pyongyang Group 3 - 39° 5'54.07"N 125°57'1.50"E. This is a group of three tunnels that are all located within the same hill, encircling it.
4. Pyongyang Single UGF - 39° 6'43.85"N 125°58'24.30"E
5. Taedonggang Large UGF - 39°10'25.07"N 125°56'43.60"E
6. Taedonggang Smaller UGF - 39°10'31.77"N 125°56'46.76"E
7. Samdung UGF - 39° 1'32.28"N 126°12'56.77"E
8. Rodgon-ri UGF - 38°57'54.22"N 126° 2'27.51"E
9. Sangwon UGF - 38°49'39.49"N 126° 5'23.32"E
10. Chunghwa UGF - 38°52'28.51"N 125°48'23.32"E. This UGF is within the Air Defense & Combat Command HQ complex.
11. Sunwha UGF - 39° 0'52.08"N 125°36'15.03"E
12. Kanchong UGF - 38°51'34.16"N 125°33'15.48"E
13. Kangso 1 - 38°52'55.87"N 125°30'57.91"E
14. Kangso 2 - 38°52'46.98"N 125°31'48.32"E

Here are a few examples of these underground facilities.

Patreon Special Access
Patreon supporters at the $20 tier are entitled to exclusive datasets. The Google Earth file for this post is one of those exclusive offers. This is the only nationwide map of these facilities within the public domain that contain accurate geolocation data and additional information. The file also has over 300 specific sites of interest within the various missile bases for your research pleasure. Please consider supporting me on Patreon and get access to this and other exclusive datasets.

I would like to thank my current Patreon supporters: Kbechs87, GreatPoppo, and Planefag.

--Jacob Bogle, 10/22/2019 (updated list, Dec. 24, 2020)
www.JacobBogle.com
Facebook.com/JacobBogle
Twitter.com/JacobBogle

Tunnel Construction Near Reconnaissance Base

The Oryu-ri Reconnaissance Base is located in western Pyongyang on the slopes of Mt. Ryongak (Ryongaksan) at 39.018886° 125.631910°.

The administrative center of the base along with one of the large communication dishes (left) as seen via Google Earth on Nov. 8, 2019.

Very little is publicly known about the facility and even the James Martin Center for Nonproliferation Studies' own Nuclear Threat Initiative database gives only a vague description of its location and describes it as a missile base (admittedly, there are only a couple old sources available). However, the National Geospatial Intelligence Agency's GEOnet Server does verify that a place by Mt. Ryongak is called Oryu-ri (Oryu Village). 

The NGA's name database along with the NTI's general location description both fit the area and I am confident that NTI is describing what is not a missile base as such, but some kind of reconnaissance/signal intelligence base. Oryu-ri may play a role in missile defense, but it is not where missiles are launched.

Anyway, the base covers approximately 80 hectares and has existed since at least 1985 based on Landsat imagery. The facility consists of two very large communication dishes (with a diameter of 28-29 m) as well as two smaller ones. It has a clearly identifiable entrance gate and an administrative area, but what is more interesting to me is the fact that it has two large tunnels going into the mountain.

The crowded area around Mt. Ryongak

Despite its apparently clandestine activities, Oryu-ri isn't in a super remote area. The southern side of Ryongaksan, where the base lies, is also home to two camps of the Korean Children's Union, a Juche Academy, and the National Gifts Exhibition Hall (constructed in 2010-2011).

In 2019, just 350 meters from the main gate, a new set of apartments were constructed. An unidentified but suspected new national archives complex was also built nearby at the same time.

Adding to things is that on the northern side of the mountain are three military-related facilities and the Security University of North Korea. All of this means a lot of people moving around the vicinity of the base.

This brings me back to the underground sites.

Despite having external buildings, most of the real operations of the base appear to go on beneath the mountain. Outside, there's an assembly hall, some agriculture-related structures, and each of the main satellite dishes has its own control building, but I can't point to anything that might be where the signals intelligence are gathered, stored, interpreted, or anything. To me, this suggests that the main operations of the base are carried out underground.

Main tunnels of the Oryu-ri Reconnaissance Base. This older image from 2011 gives some of the clearest views of these tunnels unobscured by tree cover.

Lending weight to that theory is the size of the tunnels. The two tunnels are about 12 m wide and each one has some type of support structure above the entrance, likely part of the ventilation system, meaning that the underground portion of the base is not inconsequential. In 2018, the eastern tunnel (39.021580° 125.633111°) had a structure built over the actual entry face, obscuring its view and giving added environmental protection as people go in and out.

The two tunnels are placed 275 m apart and have been placed roughly 60 meters above sea level, with the rest of the mountain looming a further 130 meters above, giving an enormous potential space inside and plenty of rock cover in the event of an attack.

Large underground facilities such as this often have smaller exit points/maintenance entrances, and Oryu-ri does indeed have at least one identifiable access tunnel on the eastern flank of the mountain at 39.024930° 125.636075°. There is a second site with an old spoils pile, indicative of previous excavation work, but the tunnel entrance may be obscured by trees or hidden with a building.

Based solely on the positions of the two main tunnels and the access tunnel, I estimate that the interior space (if it only consists of one level), is 70,000 sq. m. However, it could be as large as 80,000 or as small as 31,000, depending on the actual internal configuration. This estimate is arrived at by considering the most concise and simple geometric designs that connect the three sites, along with the topography of the mountain itself. There is no evidence that it sprawls through the whole mountain.

Back to the access tunnel.

It is the location of the access tunnel that makes this next part all the more interesting in my mind.

Initial excavation work at both sites as seen on Oct. 4, 2016.

Beginning in 2016, initial excavation work began on a new tunnel ~330 meters north of the identified access tunnel and in the same area as the suspected second UFG access tunnel (39.027561° 125.634293°). At the same time, more excavation work could be seen just behind the Security University, 1.3 km away at 39.039439° 125.631268°.

Moving forward to 2020, a lot of progress had been made constructing the tunnel and a smaller construction access tunnel had also been added between the two main entry points of this new, larger tunnel, which is a common feature of long tunnels of every kind. 

This new, large tunnel is approximately 10 meters wide and has two probable courses. One is simply a (mostly) direct line from Point A to Point B which would take it almost right beneath the National Gift Exhibition Hall, and the other would have the tunnel more closely follow the internal bend of the mountain, allowing for maximum overhead coverage and without risking the structural integrity of any other buildings.

The white line shows the most probable direct path of the tunnel. The blue line shows a more inward curve within the mountain and has greater overhead rock coverage.

Because the new tunnel is located so close to the Oryu-ri base, with its location next to the base's UGF access tunnel, and that it comes out at a national security university, it raises these questions:

1. Does the new tunnel directly connect to Oryu-ri's underground facility? 
2. Could it be part of an expansion of the underground base?

3. Does it indicate joint activities between Oryu-ri and the Security University?

4. Or is it simply a future shortcut to the university from the new subway stations that are being built along the Hyoksin-Kwangbok subway line extension 2-3 km away from Oryu-ri?

This most recent Google Earth image shows clear tunneling work of a size capable of allowing vehicle traffic to pass through the tunnel.

Time will tell, particularly if the access road going from the Oryu-ri side of the new tunnel gets repaved and realigned to fit the other roads in the area, which would better connect it to future subway stations. Until then, we're left with yet another tunnel without an immediately clear purpose. 

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

--Jacob Bogle, 10/8/2021

AccessDPRK.com
www.JacobBogle.com
Facebook.com/JacobBogle
Twitter.com/JacobBogle

The Evolution of Kim's Underground Airbase

There are 20 air bases and one heliport with underground facilities within North Korea, however, one of those air bases stands out from the rest. While the others simply have maintenance taxiways that take aircraft away from the main runway and to underground facilities for their maintenance, resupply, and general protection, the air base at Kangda-ri (near Anbyon) actually has a runway that goes completely through a mountain. It is one of only two of its kind in the country (the other being Onchon, S. Pyongyang).

Kangda-ri has existed since at least 1984 based on Landsat images. At the time, it was just a simple dirt runway with the mountain some 500 meters off to the east. Basic work on the secondary runway which goes through the mountain appears to have began around 1997-98. Work soon stalled but was restarted in 2000. Additional work occurred in 2009-2010 and since then, almost nothing. However, imagery from late 2018 shows that new work has commenced.

1984 satellite image of Kangda-ri. The small dirt runway is barely identifiable as a thin line running parallel to the river.

By 1998, clear evidence of tunneling work under the mountain can be seen.

By 2001, the main tunnel through the mountain has been cut and the runway is beginning to extend out both sides of the mountain.

Imagery from 2002 is of high enough resolution to show detailed construction work.

This image shows two main features. First, that blast doors were installed. These will, theoretically, protect the tunnel from attack. The second is that the tunnel employs a very clever but simple design: having two ceilings. The first ceiling is simply the exposed stone of the tunnel, the second is a separate concrete arch. This "tunnel within a tunnel" acts as a shield and protects whatever is inside the tunnel from debris and small collapses of the outer stone tunnel should the mountain be bombed. This type of design was employed by the Nazis to protect key naval and missile facilities and has been used by other nations, like the US in the construction of Cheyenne Mountain.

The original runway was then upgraded in 2009-10 to a larger paved runway.

The original runway was approx. 5,400 feet long and 70 feet wide. The upgraded runway that was completed in 2010 is substantially larger at approx. 8,200 feet long and 145 feet wide.

Construction work on a bridge and road to connect the two runways actually began sometime before 2007 but was never completed. Additionally, it seems that this larger runway was abandoned as it has been overgrown and repeatedly flooded. Minor activity of various kinds can be seen between 2010 and 2017 at the underground site, but no further substantial work happened until 2018.

By 2018 several changes could be seen. 1) the pile of spoils (debris) from tunneling work has grown; 2) the southern section of runway has been resurfaced; and 3) there is an extension protruding to the west off of the northern section of runway.

The current dimensions of the extension is approx. 455 feet long and between 75 and 105 feet wide (depending on the section measured). There's no way to know what it's for at this point and based on the mind-numbing slow pace of work here, we may not know for a very long time, if the place is ever even finished. However, the fact the regime has continued to expend resources here across two generations of leadership shows that the site retains some level of importance.

The exact purpose of Kangda-ri is unknown, although we do know that it is part of the 2nd Air Combat Division (HQ at Toksan).
According to Joshua Stanton over at Free Korea, the underground runway is both too short and not wide enough for fighter jets. But, the Anbyon region is suspected to hold a major chemical weapons storage facility, so perhaps the smaller runway is supposed to be part of loading and transport. Smaller aircraft can then be lined up and taxi to the main runway (should the bridge ever be completed) where they can take the weapons to any other part of the country when needed. At this point, it's all conjecture.


--Jacob Bogle, 5/14/2019
www.JacobBogle.com
Facebook.com/JacobBogle
Twitter.com/JacobBogle

Nuclear Infrastructure: Yongdeok High Explosives Test Site

Deep in the western hills and mountains of North Korea lies a large fenced-off complex that occupies an entire valley. Just 7.4 km from the ancient city gate of Kusong is the Yongdeok High Explosives Test Site. (Note: it is alternatively spelled Yongdoktong.)

This facility was constructed in the 1980s and conducted numerous conventional explosive tests as part of North Korea's nuclear weapons program in the 1990s. The testing of these high explosives relates to the conventional explosive materials that make up the "lenses" within nuclear devices that compresses the fissionable core, initiating criticality and the nuclear explosion.

Kim Jong Un standing beside what has been humorously called the "disco ball", the primary stage of a nuclear device. The small circles are the locations of each polygonal, high explosive lens.

Explosive lens design and testing used to occur at the Yongbyon Nuclear Scientific Research Center but was later moved to Yongdeok once the complex became operational. As a dedicated testing and production center, Yongdeok is spread out over an area of approx. 6.3 square kilometers, with discreet facilities for the various research, design, testing, and production centers. 

It is suspected by senior US intelligence officials that Yongdeok's purpose has expanded over time, particularly since North Korea's early nuclear tests, to also become the country's primary nuclear warhead storage facility as well as its nuclear warhead assembly center.

Overview of Kusong and Yongdeok. 

There are different kinds of high explosive lens testing that can be done. These tests consist of more than just setting off a shell of explosives but involve creating an analogue core (to replicate the effects of the explosion on a real nuclear core) and recording the results in minute detail to ensure proper design and physical affects.

The simulated cores can be made up of inert, depleted uranium or even titanium. The cores are then surrounded by an explosive shell (made up of between 2 and 96 individual lenses) and the shell detonated. This compresses the metal core at temperatures so high that the core melts and reacts similarly like the real thing - just without the ensuing blast and destruction.

This kind of testing is called hydrodynamic because the core liquifies, and it has been the most common way to test this part of a nuclear device without needing to set off an actual bomb. Monitoring the implosion millisecond-by-millisecond is also energy intensive, and the entire process requires advanced technical skills.

With that said, the production sector does have a large electrical substation in the area to provide electricity and that could support modern testing (which can't be detected by outside parties). But the exact building this might occur in hasn't been publicly identified. It's also possible the tests happen in an underground test chamber.

The Yongdeok High Explosives Test Site with its main sectors highlighted.

Yongdeok can be generally divided into two main sectors, an administrative sector and a production sector which also has a residential district and is likely where testing takes place.

Yongdeok's administrative sector (2003).

Within the administrative sector are two main compounds, the administrative compound and the main security compound for Yongdeok. The administrative center will, undoubtedly, not only have offices dedicated to overseeing operations at Yongdeok but also to liaise with the multiple other nuclear research facilities throughout the country, and to develop new lenses (components, geometry, etc. to fit newer warhead designs). 

Yongdeok's production and testing area (2003).

In the production sector are the main industrial and testing areas as well as the largest housing district within Yongdeok.

There are multiple storage and handling facilities for explosive materials, assembly buildings, a large electrical substation, and other support buildings.

Yongdeok housing district (2003).

In 2003, this housing district included twelve single-story houses, eleven three-story apartment blocks, and a single-story multifamily home. These would provide space for approximately 148 families of scientists, engineers, technicians and other personnel.

Yongdeok housing district (2012).

By 2012, four additional houses were built next to the original cluster of eight homes, and a further 26 single-family houses were constructed across from the main district, bringing the total to 178 housing units in this area.

Explosives handling area (2003).

In this part of the production sector, eleven structures were protected by berms in 2003. Some are simply storage for raw materials, others for mixing and creating the final explosive mix, and still others for additional purposes.

However, the buildings within the "area of interest" box will undergo a change in the years ahead.

Explosives handling area (2012).

By 2012, the two long buildings within the area of interest had been replaced by five smaller storage structures protected by a berm. However, the activities within the long buildings may have simply been transferred to a new, single long building that was built a few meters away from the originals.

The reasons for this development likely had to do with safety or a change in the materials being handled at this site. 

Area that will eventually host an underground facility. (2003)

Yongdeok has multiple underground and hardened structures, but the most interesting and possibly largest is located at 40.030719° 125.307414°.

Two entrances are clearly visible in this 2017 image.

Sometime between 2003 and 2012, North Korea constructed this underground facility across from an unidentified set of industrial buildings. 

Normally, reviewing low-resolution LANDSAT imagery can help pinpoint a construction year as tunneling work results in large amounts of spoil (debris), which is typically dumped nearby. However, I can't find any clear signs of construction work, which means North Korea took specific care to limit what could be seen via remote observation. This probably included the use of netting to obscure the area and the removal of debris by trucks - leaving directly from the excavation site and not allowing any of it to pile up.

Underground entrance in 2021. Note, a building now covers the entrances.

The entrances are spaced ~13 meters apart and are large enough to accommodate motor vehicles. But, in 2020, the entrance was obscured by a new building. Reported on by CNN and Arms Control Wonk, the 35-meter-wide building covers the entrances but doesn't block them, and the building actually extends back into the hillside with the two entrances still very much visible. 

The purpose of the underground facility isn't publicly known. Whether it's testing, assembly, storage, or something else, the UGF continues to play an apparent central role in activities at Yongdeok.

Agricultural area (2017).

Large parts of Yongdeok are actually cultivated fields and small greenhouses, as very little cleared land in North Korea is allowed to lay fallow. The grounds next to the administrative compound are no exception. In 2017, the area held a small park but most of the land were fields. 

Agricultural area in 2023.

By 2023, a segmented garden area covering 1.2 hectares was established and three larger greenhouses were built along with two additional buildings. At the park, swimming pools were installed.

Gardens similar to this have been popping up around North Korea for the last decade or so. The food can either be grown to supplement the diets of those living in the area or grown as crops for sale (domestically or even for export), but it's most likely in this case that they're being grown to supply Yongdeok.

Probable COVID quarantine facilities (2021).

As I first hypothesized on AccessDPRK and then confirmed with NK News, North Korea built scores of COVID quarantine centers around the country. They all share the same visual signatures: external guard posts, an outer fence, and an inner wall. Sometimes they converted existing structures and other times purpose-built facilities were constructed. 

Most of these isolation centers are civilian, but some can be found at military bases. And for Yongdeok, a total of three exist, with two being built next to each other in 2021.

Detail of Site 2. 

Usually, a whole town might only have one of these secured quarantine facilities, but Yongdeok has three (the third is located at 39.993325° 125.341502°). This could be because of the national security risk posed by having a pandemic decimate the skilled population that lives and works at the site that they wanted to ensure enough treatment space was available. 

It could suggest that COVID not only hit Yongdeok but did so particularly badly, necessitating additional sites. Or maybe there's three because each one provides a larger space to patient ratio (individual rooms perhaps instead of the rows of beds at civilian facilities), so they simply needed to build more to have the required space. 

In any case, the placement of quarantine facilities at Yongdeok underscores the importance the regime places on it. Such facilities haven't been located at ballistic missile bases or even at most other military sites (including Punggye-ri). But Yongdeok has three.

In all, Yongdeok is comprised of hundreds of buildings, its own security infrastructure, and has facilities for storing and manufacturing explosive material, testing the lenses, research and development, and assembly and storage of nuclear devices. There are also enough residential units to house approximately 1,100 individuals on-site (including family members).

Yongdeok plays a critical role in North Korea's nuclear program and will for the foreseeable future. Although details of the activities at the site are unknown, satellite imagery offers us a window into one of the most secret locations in the country.

And, who knows, after Kim showed off the Kangson Uranium Enrichment Plant for the first time, maybe we'll get an official look at Yongdeok one day. 

I would like to thank my current Patreon supporters who help make all of this possible: Donald Pearce, David M., Dylan D, Joe Bishop-Henchman, Joel Parish, John Pike, Jonathan J., Kbechs87, Raymond Ha, Russ Johnson, Squadfan, and Yong H. 

--Jacob Bogle, October 26, 2024

AccessDPRK.com
www.JacobBogle.com
Twitter.com/JacobBogle