The Tonghae Satellite Launch Ground, also known by “Musudan-ri” due to its proximity to the area, is one of North Korea's major rocket test-launch facilities and has been used to flight-test a variety of missiles and satellite launch vehicles. Since becoming operational, the site has flight-tested the Hwasong-5 and Hwasong-6, Nodong, Taepodong‐1 and Taepodong-2 missiles. The most recent tests occurred in May 2009 hours after North Korea’s second nuclear test when three short-range surface-to-air missiles were launched from the site.[1]

Construction began around 1982 or 1983, and North Korean defector Im Yeong Seon (임영선) believes construction of the launch pad was completed in 1985.[2] However, Jane’s asserts that the facility was operational and began conducting test launches as early as 1984.[3]

North Korea used the Tonghae Satellite Launch Ground for testing long-range rockets. In 1998, North Korea attempted to launch the Kwangmyongsong-1 satellite into orbit using a Taepodong-1 from the Tonghae site. The 3^rd stage of the rocket failed, however North Korea still claimed that the satellite went into orbit.[4] North Korea launched Taepodong-2 rockets in 2006 and 2009, also resulting in failures.[5]

Tonghae Satellite Launch Ground’s infrastructure has been updated numerous times over the last two decades. The first major expansion was completed in 1999, when the launch tower’s height was expanded from 22 meters to 33 meters.[6] In 2008, satellite imagery revealed that the missile assembly building was extended by 28 meters. These images also showed that the access road leading to the missile assembly building was expanded. These expansions resulted in the facility being capable of simultaneously storing two Taepodong-2 launch vehicles. The expansions will also “allow for the assembly of larger missile systems.”[7] In 2009, Digital Globe, a private US-based space imagery firm, released images of the site which revealed a missile assembly building, launch tower, and a rocket engine testing stand. The imagery also revealed the absence of paved roads leading to the facility as well as a lack of personnel housing.[8]

Throughout the late 1990s and early 2000s, numerous rocket engine tests for the Taepodong-2 were conducted at Tonghae Satellite Launch Ground.[9] In 2002, a mysterious explosion occurred during a rocket engine test. The explosion damaged both equipment and the facility’s physical infrastructure.[10] The site has since been repaired. However, a transition appears to be underway to make the recently completed Sohae Satellite Launching Station the primary site for long-range ballistic missile launches.

Sources:
[1] "DPRK Test‐Fires Short‐Range Missile After Nuclear Test," Xinhua, 25 May 2009, via: www.lexisnexis.com.
[2] Interview with North Korean defector Im Yeong Seon by Daniel A. Pinkston, senior research associate, Center for Nonproliferation Studies, 14 December 2001, Seoul.
[3] “North Korea's Musudan-ri Launch Site Looks Primitive,” Jane's Missiles and Rockets: Strategic & Sub-Strategic, 1 February 2000.
[4] Joseph S. Bermudez Jr., “Going Ballistic - North Korea's Advanced Missile Capabilities,” Jane's Intelligence Review, 12 March 2009.
[5] “U.S. officials: North Korea Tests Long-Range Missile,” CNN, 4 July 2006, http://articles.cnn.com; William J. Broad, “North Korean Missile Launch Was a Failure, Experts Say,” The New York Times, 5 April 2009, www.nytimes.com.
[6] Joseph S. Bermudez, Jr., "North Korea's Musudan-ri Launch Facility," Center for Defense and International Security Studies, 1999, www.cdiss.org.
[7] “Musudan-ri Missile Test Facility North Korea: February 15, 2002 – March 26, 2009,” Global Security, www.globalsecurity.org.
[8] “Musudan-ri Missile Test Facility North Korea: February 15, 2002 – March 26, 2009,” Global Security, www.globalsecurity.org.
[9]  Pak Tu-sik and Yu Yong-won, "박두식, 유영원, "미, 북 미사일 감시제제로, [US Turned on Missile Monitoring System]," Chosun Ilbo, 6 February 2002, www.kinds.or.kr.
[10] "Explosion Hit North Korea Missile Test Site: Report," Agence France-Presse, 21 April 2003, via: www.lexis‐nexis.com.