Koh Samui, often simply Samui as it is referred to by locals, is an island off the east coast of the Kra Isthmus in Thailand, close to the mainland Surat Thani town. It is Thailand's third largest island, with an area of 228.7 km2 and a population of over 50,000 (2008). It is rich with natural resources, white sandy beaches, coral reefs and coconut trees.

The island measures some 21 kilometres at its widest point, and 25 km at its longest. It is surrounded by about sixty other islands, which compose the Ang Thong Marine National Park (Mu Ko Ang Thong National Park) and include other tourist destinations (Ko Pha Ngan, Ko Tao and Ko Nang Yuan).

Source: Wikitravel