Northern Limit Line mainland portion reverted to North Korean control, while the islands remained a part of South Korea despite their close proximity. The line extends into the sea from the Military Demarcation Line (MDL), and consists of straight line segments between 12 approximate channel midpoints, extended in an arc to prevent egress between both sides. On its western end the line extends out along the 38th parallel to the median line between Korea and China. The 1953 Armistice Agreement, which was signed by both North Korea and the United Nations Command (UNC), ended the Korean War and specified that the five islands
Australia in the Korean War 1st Commonwealth Division and the 1st South Korean Division) seized the Jamestown Line destroying elements of the 42nd Army, 47th Army, 64th Army and 65th Army, and after five days of intense combat, eventually forcing the Chinese into retreat. The operation was a success, and ended on 15 October, with a few hills south of the line still in Communist hands, requiring a follow-up operation (Operation Polecharge). The official historian for the Korean War, Robert O'Neill, wrote of this battle: "In this action 3RAR had won one of the most impressive victories achieved by any Australian battalion. In five days