Military Demarcation Line



The Military Demarcation Line (MDL), sometimes referred to as the Armistice Line, is the land border or demarcation line between North Korea and South Korea. On either side of the line is the Korean Demilitarized Zone (DMZ). The MDL and DMZ were established by the Armistice at the end of Korean War in 1953.

In the Yellow Sea, the two Koreas are divided by a de facto maritime "military demarcation line" and maritime boundary called the Northern Limit Line (NLL) drawn by the United Nations Command in 1953. The NLL is not described by the Korean Armistice Agreement.

Demarcation on land
The DMZ runs near the 38th parallel, covering roughly 248 kilometers. American and South Korean soldiers patrol this line along the South Korean side while North Korean soldiers patrol along the North Korean side.

In Korean, the line is called the Hyujeonseon (휴전선), meaning "armistice line." It is also sometimes called the Gunsa Bungye-seon (군사분계선), which literally means "military demarcation line." However, in colloquial usage, the dividing line is more often called the Sampalseon (삼팔선, "38th parallel"), a name likely coined at the end of World War II, when it would have been an accurate description of the North-South border.

The line itself is marked off by a series of 1,292 identical signs which are placed at intervals across the peninsula. The north facing side of the signs are written in Korean and Chinese, and in Korean and English on the south facing side. The signs are aging and rusting.

Military incidents
There have been frequent skirmishes along the line since the armistice ended the fighting of the Korean War.

Usage and conventional misuse
The Korean Armistice Agreement is the primary source which defines the MDL; and 21st century scholarly/academic secondary sources continue to recognize this as fundamental. The Armistice is monitored by members of the Neutral Nations Supervisory Commission composed of members from the Swiss and Swedish Armed Forces.

Military Demarcation Line is a de jure term and MDL is an explicit acronym which remain valid today because no mutually acceptable changes have been made. The use of the term or acronym or line which is not explicitly mentioned in the 1953 KAA is not verifiable within the ambit of the primary source text.

The unresolved aftermath of the Korean War has revealed unique, region-specific facets of this conflict. Although the Korean Armistice Agreement specifies where the demarcation line and demilitarized zone are located on land, the agreement does not mention lines or zones in adjacent ocean waters.

Historical context
Map of Korean maritime border.svg between North and South Korea in the Yellow Sea:

A: United Nations Command-created Northern Limit Line, 1953

B: North Korea-declared "Inter-Korean MDL", 1999

The locations of specific islands are reflected in the configuration of each maritime boundary, including 1–Yeonpyeong Island2–Baengnyeong Island3–Daecheong Island

4-Jung-gu (Incheon Intl. Airport), 5-Seoul, 6-Incheon, 7-Haeju, 8-Kaesong, 9-Ganghwa County, 10-Bukdo Myeon, 11-Deokjeokdo, 12-Jawol Myeon, 13-Yeongheung Myeon ]]

Shortly after the signing of the Armistice, a line in the sea was drawn unilaterally by the United Nations Command (UNC). The contrived Northern Limit Line or North Limit Line (NLL) represents the northern limit of the area in which South Korean vessels may navigate, not a demarcation line on which the two Koreas agreed. The Korean Armistice Agreement (KAA) provisions regarding the MDL and DMZ do not extend into the Yellow Sea or Sea of Japan.

In 1999, North Korea unilaterally asserted its own "North Korean Military Demarcation Line in the West Sea (Yellow Sea)", also called the "Inter-Korean MDL in the Yellow Sea".

The 1953 MDL is a demarcation line, and the 1953 NLL is a demarcation line as well; however, the MDL is a different line than the NLL. The 1999 North Korean MDL is also distinct. Across a span of decades, precision has been blurred by conventional usage and reports in the popular press. "Two Killed In Sea Crash," St. Joseph Gazette (US). December 24, 1962; excerpt, "The gunboats clashed near Island in the Yellow Sea just south of the military demarcation line, the South Korean announcement said"; "Ships Trade Fire I With Reds," News And Courier (US). May 28, 1967; excerpt, "The shelling occurred near the military demarcation line separating North and South Korea. A ROK spokesman said that ships were in the area to protect fishing boats"; "Red Korea Seizes Boat, 20 Crewmen," Free Lance-Star (US). June 5, 1970; excerpt, "The general area is near the seaward extension of the military demarcation line that separates South Korea from the Communist North"; "In Korean Flareup," Miami News (US). February 27, 1975; excerpt, "... North Korean vessels found cruising about 20 miles south of the extension of the military demarcation line between the two Koreas"; "North Korea Returns 12 South Koreans," Toledo Blade (US). October 20, 1985; excerpt, "... fishing in international waters waters about 40 miles west of the South Korean island of Paeknyong-do near the western sea extension of the military demarcation line dividing the Koreas"

Maritime demarcation
Some now construe the existence of a de facto or "practical" extension of the 1953 MDL.

After more than fifty years, the South Koreans have come to construe a de facto western inter-Korean border which has remained unchanged since 1953. The map at the right shows that the ambits of the NLL and North Korea's maritime MDL represent overlapping jurisdictional claims. The DPRK rejected the NLL and only recognized the demarcation line it drew in 1999, which was further south of the NLL.