The Four Islands Tour is Krabi's most popular day excursion, hopping between Koh Mook, Koh Ngai, Koh Chuak, and Koh Waen — four small islands in the southern Trang-Krabi sea corridor, each with distinct character. The tour visits Tham Morakot (the Emerald Cave) — a sea cave accessible only by swimming through a dark 80-metre tunnel that opens into a hidden beach inside a jungle-filled lagoon. Snorkelling stops at coral gardens between the islands complete the day.
Highlights
- Tham Morakot (Emerald Cave) — swim through darkness to a hidden beach inside a hollow mountain
- Snorkelling at pristine coral gardens between the four islands
- White sand beaches on Koh Ngai and Koh Mook
- Floating lunch stop in a calm bay between islands
How to Get There
Tours depart from Ao Nang Beach, Krabi Town Pier, and several Ao Nang piers daily. Book through any guesthouse, tour agent, or directly at the pier. No independent access exists to all four islands — the longtail loop route is tour-only.
Visitor Tips
The Emerald Cave swim is 80 metres through complete darkness — a head torch is provided but the experience is genuinely disorienting. Do not attempt if you are claustrophobic.
Snorkel early at each stop before the boats churn up the water.
Confirm your tour includes Tham Morakot — some budget operators skip it.
Frequently Asked Questions
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Senior Travel Writer · Bangkok · 12+ years in Thailand
James has lived in Bangkok since 2014 and has visited all 77 Thai provinces. He specialises in destination guides, itinerary planning, and transport logistics. Before moving to Thailand, he worked as a travel journalist in Hong Kong and Singapore. He speaks conversational Thai and is a certified PADI divemaster.
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