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National Parks·Khao Lak

Similan Islands

Thailand's premier diving and snorkelling destination — crystal clear water in the Andaman Sea

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The Similan Islands (Mu Ko Similan National Park) form an archipelago of nine granite islands 70 km off the Phang Nga coast in the Andaman Sea. They are consistently ranked among the world's top ten diving destinations, with visibility commonly exceeding 30 metres, water temperatures of 28–30°C, and coral diversity that was largely undamaged by the 1998 bleaching event that affected much of the Indian Ocean.

The islands are accessible only from Khao Lak or Phuket by speedboat or liveaboard, and the park closes from May to October to allow reef recovery. Within the national park, accommodation is limited to park bungalows and camping on a few islands — the majority of visitors arrive on day trips from Khao Lak (90 minutes by speedboat) or join multi-day liveaboard diving trips.

Above water, the islands are equally beautiful: white sandy beaches backed by jungle-covered granite boulders, absolute clarity of water, and near-complete absence of commercial development. Snorkelling directly off the beach is excellent. The combination of accessible marine life for snorkellers and world-class dive sites at depth makes the Similans suitable for all levels.

Highlights

  • World-class diving with 30-metre+ visibility in season
  • Pristine coral reefs relatively undamaged by bleaching events
  • Excellent snorkelling directly off beaches
  • Dramatic granite boulder landscapes on beaches and in the water
  • Green and hawksbill turtle sightings at multiple sites
  • Complete absence of commercial development on the islands

How to Get There

All boats depart from Tab Lamu pier near Khao Lak, Phang Nga province (1.5 hours north of Phuket airport). Day trip speedboats take 90 minutes to the islands. Phuket-based tours include a 1.5-hour drive to the pier. Liveaboard departures are primarily from Khao Lak and Phuket.

Visitor Tips

1.

Liveaboard trips (3–4 days) provide the best access to premier dive sites and the least-visited islands — significantly better than day trips.

2.

Day trips depart from Khao Lak pier (90 minutes) and from Phuket (3+ hours) — Khao Lak departures are notably more comfortable.

3.

Book in January or February for the best sea conditions and highest visibility.

4.

Reef shoes and gloves are not permitted in the national park — no touching of coral.

5.

The park opens in November but conditions (sea state) are most reliable from December.

Dress Code Required

Swimwear; rash guard recommended for sun protection and jellyfish

Frequently Asked Questions

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James Chen

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.

Our editorial standards

Visit Information

🕐
Hours
Open November to April only (park closed May–October)
💰
Entry Fee
500 THB national park fee (usually included in day trip packages)
⏱️
Time Needed
Day trip minimum; liveaboard for full dive experience
📅
Best Time to Visit
December–March for calmest seas and best visibility
👔
Dress Code
Swimwear; rash guard recommended for sun protection and jellyfish

Nearby Attractions

Khao Sok National ParkRailay Beach

Destination Guide

See the full guide to Khao Lak for hotels, restaurants, and transport.

Khao Lak Guide
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