Ko Tao or Turtle Island; located in the midst of the Gulf of Thailand; was named by early settlers for the island's hump-backed; turtle-like shape; though it is also a significant breeding ground for both Hawksbill and Green Turtles.

The economy of the island; which was once uninhabited except for transient fishermen; now revolves almost exclusively around tourism and scuba diving. The rapid development of tourism in recent years has had a negative impact on turtle breeding; but since 2004 the Royal Thai Navy in conjunction with a cooperative of local dive centers has sponsored the reintroduction of hundreds of juvenile turtles to Ko Tao's ecosystem.

The island is about 21 sq km (8 sq miles) in area; and the main settlement; on the western side of the island; is Ban Mae Hat. Most of the island is rugged; with dense forest inland; quiet coves along the relatively difficult-to-reach east coast; and a fine sweep of sandy beach along the western shore.