Geography of Vietnam

Vietnam is located on the eastern margin of the Indochinese peninsula and occupies about 331,211.6 square kilometres (127,881.5 sq mi), of which about 25% was under cultivation in 1987. It borders China, Laos, and Cambodia and has shorelines along the Gulf of Tonkin, Gulf of Thailand, and Pacific Ocean. The elongated roughly S shaped country has a north-to-south distance of 1,650 km (1,030 mi) and is about 50 km (31 mi) wide at its narrowest point. With a coastline of 3,260 km (2,030 mi), excluding islands, Vietnam claims 12 nautical miles (22.2 km; 13.8 mi) as the limit of its territorial waters, an additional 12 nautical miles (22.2 km; 13.8 mi) as a contiguous customs and security zone. It has an exclusive economic zone of 417,663 km2 (161,261 mi2) with 200 nautical miles (370.4 km; 230.2 mi).

The boundary with Laos was settled on both an ethnic and geographical basis between the rulers of Vietnam and Laos in the mid-seventeenth century. The Annamite Range as a reference, was formally defined by a delimitation treaty signed in 1977 and ratified in 1986. The frontier with Cambodia, defined at the time of French annexation of the western part of the Mekong Delta in 1867, remained essentially unchanged, according to Hanoi, until some unresolved border issues were finally settled in the 1982–85 period. The land and sea boundary with China, delineated under the France-China treaties of 1887 and 1895, is "the frontier line" accepted by Hanoi. China agreed in 1957–1958 to respect that border line.