Koh Samui Angthong Marine Park

Ang Thong National Marine Park is one of Thailand's most breathtaking protected areas, comprising 42 islands of the inner Gulf of Thailand covering 102 square kilometres. The park's dramatic scenery — limestone mountains covered in thick jungle rising straight from the sea, hidden caves, and perfectly secluded beaches — was the inspiration for Alex Garland's novel 'The Beach'. The day trip by speedboat from Koh Samui includes snorkeling at the park's coral gardens, sea kayaking through natural sea arches and limestone caves, hiking to the viewpoint of Mae Ko Island for a panoramic view of all 42 islands, and swimming in Talay Nai — a landlocked emerald lake connected to the sea through a natural underground passage. The emerald-green colour of the lake is extraordinary and unlike anything else in Thailand.