Also called the Armistice Line, the Military Demarcation Line (MDL) is the land border between North and South Korea. It is also sometimes referred to as the Armistice Line or, in Korean lingo, the Sampalseon (38th Parallel). On either side of the MDL is the Demilitarized Zone (DMZ). The MDL is marked by more than 1,000 signs (see one below) ranging across the Korean peninsula. A concrete slab between the conference buildings on the Joint Security Area designates the MDL there. The DMZ and MDL were established by the Armistice, and the related oceanic Northern Limit Line (NLL) was drawn by the United Nations Command. The area immediately along the MDL has been the site of many military incidents and linked to various buffer zones, no-fly zones, and Yellow Sea peace zones.