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US Army Garrison Yongsan
Yongsan Army Garrison

US Forces Korea Facilities

Related Facilities


The U.S. Forces Korea(USFK) opened its new headquarters in Pyeongtaek, Gyeonggi Province on 29 July 2018. The relocation from Yongsan in central Seoul came 73 years after the USFK headquarters were first stationed in South Korea. With the relocation, the United Nations Command and US Forces Korea were leaving Yongsan, their home for the past six decades, and plan to complete their move to Camp Humphreys, by the end of 2018. Meanwhile, the ROK-US Combined Forces Command will relocate to a building inside South Korea's defense ministry in central Seoul by the end of 2018.

Yongsan Garrison is located in the heart of the capitol city of Seoul, South Korea. Although Seoul boasts a population of over 11-million, Yongsan Garrison enjoys the life-style of a suburb of a small city. Within the Seoul area there are numerous posts and camps. The biggest installation is Yongsan, which is the headquarters for the US military presence in Korea. The Yongsan Garrison is home to the quad-headquarters of the United Nations Command, US-ROK Combined Forces Command, United States Forces Korea and the Eighth United States Army. In addition, tenant units to include all headquarters for the Major Subordinate Units are located in Yongsan.

During the Japanese occupation of the Korean Peninsula from 1910 to 1945, the Imperial Japanese Army made its headquarters at Yongsan Reservation near the Han River in a southern suburb of Seoul. After Japan surrendered to end World War II in 1945, US military units were sent to the Korean peninsula to accept the surrender of the Japanese forces in the area south of the 38th parallel. North of that line, Soviet troops took over from the Japanese. One area the arriving American units moved into was Yongsan, which means Dragon Mountain. US military occupation forces, led by XXIV Corps and the 7th Infantry Division, provided order, security and administration of the government pending establishment of a single government for the entire peninsula.

A unified Korea proved impossible as the Soviets moved to seal the border at the 38th parallel and create a communist state in the northern zone. In 1948, following approval of a new constitution and elections monitored by the United Nations, the Republic of Korea government replaced the existing government defending the ROK.

The Yongsan area continued to be used by members of the US forces, this time serving in an advisory role. The Korean Military Advisory Group (KMAG) was formed in 1949 at the request of the ROK Government to help develop and train security forces.

The North Korean invasion in June 1950 turned all of Korea into a battlefield. Yongsan Reservation, like other areas of Seoul, sustained substantial damage. The opposing forces each moved through the capital city twice before the United Nations Command regained control.

With the war stalemated, UNC and US Forces established headquarters at Yongsan in 1952, having control over some 630 acres of the former Japanese headquarters. An administrative headquarters which was eventually known for almost two decades as the Seoul Area Command, or SAC ran the post itself.

In July 1957, Headquarters, US Forces Korea was established. At the same time, Headquarters, United Nations Command, located in Tokyo, was moved to Yongsan.

Many buildings used by the Japanese Army were still in use. A few examples: The JUSMAG building used to be the Japanese army hospital. The Japanese cavalry and horse stables were located at what became Hannam Village. Eighth Army Special Troops Headquarters building was an officer's club. The 5 2-storied brick buildings on main post that housed HQ United States Forces Korea and Eighth US Army headquarters and various staff sections served similar purposes for the Japanese army.

Traces of the Japanese occupation were erased from Yongsan as was the war damage that once was readily seen on perimeter walls and buildings. The continued presence of US forces in partnership with the ROK forces brought many changes to the installation, first, corrugated tin Quonset huts that sprouted in clusters in the form of a half-moon throughout Yongsan (and every other area where US Forces were stationed) and then, when US military families began to slowly appear in Korea in the 1960s and budgets permitted, in more fashionable and permanent structures.

In October 1971, the US Army Garrison Yongsan was removed from provisional status and began to expand its support capabilities. Schools, more family units and improved troop facilities were developed, only to be interrupted for several years in the late 1970s when the planned reduction of US ground combat forces tightened construction budgets. Cancellation of the reduction plan in 1980 was followed by years of improved budget situations and the transformation of Yongsan's physical plant from an olive drab cocoon to a model installation was back on track.

On 17 November 2003 the United States and South Korea agreed in principle to move most American forces out of the capital city of Seoul and south from the demilitarized zone along the border with North Korea. Defense Secretary Donald Rumsfeld was in the country's capital for the annual Security Consultative Meeting between defense officials from the two countries. The US and Korean governments agreed to move the majority of the 7,000 troop-strong American military presence out of the Seoul area onto bases farther south. A small American presence is likely to remain in Seoul, but the numbers had not been agreed to.

South Korea and the United States agreed 17 January 2004 in a meeting held in Hawaii, US, to relocate all the US troops currently stationed in Seoul. The 2 allies reached the agreement at the end of a 2-day meeting named "Future of the ROK (Republic of Korea)-US Alliance Policy Initiative" talks. All the 8,000 US troops, including the ROK-US Combined Forces Command (CFC) and the United Nations Command (UNC), would move out of Seoul to Pyeongtaek before 2006. Only the USFK general command office along with 50 relevant personnel would remain in Seoul. South Korea would shoulder all the expenses of 3 billion US dollars of the relocation.

The Department of Defense announced 23 July 2004 that representatives of the Republic of Korea and the United States finalized agreements to relocate all US Forces from the Seoul Metropolitan Area to the Pyongtaek area. The decision was reached during the 10th round of the Future of the Alliance talks held in Washington, DC. The agreement fulfilled a commitment made by President Bush and President Roh at their summit meeting in Washington in May 2003. The relocation of US forces out of Seoul was expected to be completed by December 2008.

As of mid-2004 there were approximately 8,000 US servicemembers in the Seoul Metropolitan Area. Yongsan Garrison occupied some 630 acres of land just south of Namsan Mountain. 160 tenant units occupied 1,225 buildings with a combined floor space of more than 4,750,000 square feet. Access between units was provided by 20.4 miles of paved roads. The post was divided into 3 major areas: South Post, North Post and Camp Coiner, with several smaller adjacent areas (Hannam Village, Camp Kim, the FED Compound, the Seobingo Compound, Seongnam Golf Course, and the Retreat Center). Yongsan Main Post hosted several major commands including the United Nations Command, Combined Forces Command, United States Forces Korea and the Eighth United States Army. Yongsan and surrounding installations were populated by all segments of the USFK team, soldiers, sailors, airmen and marines, as well as Department of the Army civilians, Embassy personnel, and invited contractors. Close to Seoul were Camps Red Cloud, Stanley, Casey, and Hovey to the north. Nearby to the south were Colbern, K-16 Airfield and Suwon Air Base.

Additionally, the post provided all the support facilities associated with a small city, including a hospital, a fire station, a police force, commissary and exchange facilities, schools, theaters, clubs and restaurants, a hotel, sports and recreational facilities, water and sewage treatment plants and emergency electrical power.

USFK had about 2,500 military personnel assigned to the quad-command headquarters and support agencies at Yongsan. They were augmented by about 1,000 US civilian and 6,000 Korean civilian employees. More than a thousand Korean Augmentees to US Army (KATUSA) soldiers worked at Yongsan, and some 3,500 military and civilian employee family members resided on South Post, Hannam Village, a contract housing area east of South Post, or on the civilian economy in neighborhoods adjacent to the compound.

Yongsan was supported by the 34th Support Group. The 34th Support Group's responsibilities included installation base operations and support to all units in Area II, some 22 installations and subinstallations with a supported population in excess of 23,000 personnel. Yongsan served as the entertainment hub for the peninsula with thousands of US Military and civilian personnel coming to The Dragon Hill Lodge, 121st General Hospital, Yongsan Commissary, Army and Air Force Exchange Service facilities, as well as the numerous Morale, Welfare and Recreation activities provided. The 34th Support Group and Area II includes Yongsan Garrison, Camp Colbern, K-16 Airfield, Niblo Barracks, Madison Site, FED Compound, Camp Gray Annex, Camp Market, Camp Morse, Sungnam Golf Course, CP TANGO, Kimpo Postal Facilities, Koryosan ASA, EUSA Retreat Center, and Camp Yongin.

The 34th Support Group was inactivated in September 2004. US Army Garrison Yongsan (USAG-Y) was established on 19 March 2007 in a ceremony at Lombardo Field. The Army directed redesignations in a move to standardize garrison names worldwide and the unit name was changed from the former Area II Support Activity. Prior to the redesignation, the Area II Support Activity was part of the Installation Management Agency headquartered at Yongsan Garrison in Seoul, Republic of Korea and was activated Oct. 7, 2003. The US Army's IMA was established in October 2002, and subsequently was redesignated as Installation Management Command (IMCOM), to standardize Army installations, services and support worldwide in accordance with the ongoing Army transformation.


The FASTBACK system that was replaced in Korea is reflective of the typical legacy mw systems used by the US Army to support worldwide long haul communication requirements. The FASTBACK system (seven individual links) provided a secure reliable means of transmitting bulk data collected along the Demilitarized Zone to command groups located in the southern part of the country. The equipment (i.e., radios and multiplexers) supporting the FASTBACK system had been in operation for over fifteen years, utilizing technology that was over twenty years old. The FASTBACK system consisted of an AN/FRC-162 radio and AN/FCC-97 multiplexer. In the late 1990s it was replaced by a high speed (155 Mbps) SONET digital microwave radio that utilize the digital data multiplexer (DDM)-2000 OC3 multiplexer. The Digital Microwave Upgrade DMU Phase I is a good example of what occurs when the link bandwidth is increased (8 DS1s to 84 DS1s (three 45 Mbps DS3)) with high speed SONET digital microwave and interface requirements to existing older, low speed mw technology. The Yongsan to Madison, Osan to Madison, and Camp Humphreys to Madison FASTBACK links were replaced during Phase I with the Harris MegaStar 2000 SONET radio. The remaining FASTBACK mw links between Madison and Kamaksan, Kangwhado, and Songnam, and Kamaksan and Yawolsan, were replaced during DMU Phase III. In conjunction with the DMU, the digital patch and access systems (DPAS) at Yongsan, Osan, and Camp Humphreys were upgraded to support up to three DS3s each.

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Page last modified: 10-07-2018 17:36:47 ZULU