Indonesia–Thailand border
Indonesia and Thailand share a common maritime border in the northern part of the Straits of Malacca and the Andaman Sea to the north-east of Indonesia's Sumatera Island and to the west of the western coastline of southern Thailand. The maritime boundary runs between the India-Indonesia-Thailand tripoint in the north, and the Indonesia-Malaysia-Thailand tripoint in the south. The border was delimited through four agreements, with two involving third parties India and Malaysia as they determined trijunction points with those countries. The border. Four boundary delimitation agreements are the Indonesia-Thailand continental  shelf boundary delimitation agreement of 17 December 1971; the Indonesia-Malaysia-Thailand tripartite continental shelf boundary delimitation agreement of 21 December 1971; the Indonesia-Thailand sea-bed boundary delimitation agreement on 11 December 1975; and the India-Indonesia-Thailand trijunction and related boundaries tripartite agreement of 22 June 1978. The coordinates of end and turning-points of the border are as follows:-