Ko Samui, also known as Koh Samui, is an island located off the east coast of Thailand in the Gulf of Thailand. Geographically part of the Chumphon Archipelago, it sits approximately 35 kilometers northeast of Surat Thani town. While it is administratively an amphoe or district within Surat Thani Province, the island holds municipal status and operates as a locally self-governing city municipality with greater powers of self-governance.