Ko Samui (or Koh Samui, Thai เกาะสมุย) is an island off the east coast of the Kra Isthmus in Thailand, close to the mainland Surat Thani town. It has an area of 228.7 km² and a population of 45,873 (2004).
The island was probably first inhabited about 15 centuries ago, settled by fishermen from Malaysia and Southern China. It appears on Ming Dynasty maps dating back to 1687, under the name Pulo Cornam. The name Samui is mysterious in itself. Perhaps it is an extension of the name of one of the native trees, mui, or it is a corruption of the Chinese word Saboey, meaning "safe haven".
Until the late 20th century, Samui was an isolated self-sufficient community, having little connection with the mainland of Thailand. The island was even without roads until the early 1970s, and the 15km journey from one side of the island to the other involved a whole-day trek through the mountainous central jungles.
Today, Samui has a population of about forty-five thousand, and lives on a successful tourist industry, as well as exports of coconut and rubber. It even has its own international airport, with flights daily to Bangkok and other major airports in Southeast Asia. It has not forgotten its roots, however, and the people are still by-and-large the same easygoing island folk they were before the world landed on their doorstep
Samui is located in the Gulf of Thailand, about 35km northeast of Surat Thani town (9°N, 100°E). It is surrounded by about sixty other islands, most of which comprise the Ang Thong National Marine Park, but also include other tourist destinations Ko Pha Ngan, Ko Tao and Ko Nang Yuan.
The island is roughly circular in shape, and is about 15km across. The central part of the island is an (almost) uninhabitable mountain jungle (peak Khao Pom, 635m) and the various lowland areas are connected together by a single road, that covers the circumference of the island.
There is one town, Na Thon, on the west coast of the island, with a major port for fishing and inter-island transportation. Each of Samui's many beaches is also nominally considered a town, due to the number of hotels, restaurants and bars that have sprung up in recent years.
Administratively, Ko Samui is an Amphoe (district) of Surat Thani province. The district is subdivided into 7 tambon:
Ang Thong, Li Pa Noi, Taling Ngam, Na Mueang, Ma Ret, Bo Phut, Maenam
Historically the island's economy has been based around subsistence agriculture and fishing, with coconuts as the main cash crop. From the 1980s onwards however, tourism has become an economic factor and is now the dominant industry. The construction of a stable, high-speed internet connection in recent years has also made the island a practicable location for IT-based enterprises, which are beginning to provide a certain degree of economic diversity. The island's climate and accesibility make it particularly attractive for international investors.
Samui is mostly visited by holidaymakers wanting to "get away from it all", so its main appeal is its white beaches and warm sea, and it has plenty to choose from.