Similan Islands: granite boulders and dive sites

The Andaman's most famous islands for diving and snorkelling.

Area

Island trips

Start from

Khao Lak (Thap Lamu pier)

Distance

about 1–1.5 hours by speedboat

Time needed

1–4 days

Best season

Mid-October – mid-May

Difficulty

Moderate

Transport

Speedboat or liveaboard

Tickets & rules

National park fee; daily visitor caps

Why go

The Similans are a chain of islands in a protected marine park, famous for granite boulders, white sand and rich marine life.

Sail Rock on Koh Similan is the iconic view.

Liveaboard dive trips are world famous.

Snorkelling here can mean turtles, reef sharks and huge schools of fish.

Koh Similan's Sail Rock viewpoint requires a short climb.

The islands look unlike any others in the Andaman: smooth, rounded granite boulders the size of houses tumble down to white beaches, and the water ranges from pale turquoise to deep blue. Under the surface, the boulders form swim-throughs and caves full of fish.

Day trips usually include several snorkelling stops and a beach visit, but the real Similan experience is a liveaboard dive trip of several days, reaching sites like Elephant Head Rock and the more remote Koh Bon and Koh Tachai for manta rays.

The story

The name comes from a Malay word for nine, for the original nine islands.

The park is home to Moken sea nomads' traditional waters.

The Moken, sea nomads, have long traditions in these waters.

The park was established in the 1980s.

The Similans became a national park in 1982, and since then the government has gradually tightened rules, closing islands to overnight stays and capping daily visitors to protect the reefs. The park closes completely during the monsoon, usually from mid-May to mid-October, giving nature a break.

Divers often say the Similans changed how Thailand thinks about marine protection: proof that pristine reefs are worth more alive than exploited.

Getting there

Tours from Khao Lak or Phuket.

Boats leave early; hotel pick-up from Phuket is around dawn.

A suggested plan

1. MorningSpeedboat out.
2. DaySnorkel stops and beach.
3. AfternoonReturn.
4. OptionalLiveaboard diving trips of 3–5 days.
5. MorningHotel pick-up around dawn, transfer to Thap Lamu pier in Khao Lak.
6. MiddayClimb to the Sail Rock viewpoint on Koh Similan, swim at Donald Duck Bay.

Where to stay

Khao Lak resorts.

Good to know

• Book early in high season.
• Bring seasickness tablets.
• Visitor numbers are capped; book ahead.
• Respect park rules.
• Day trips are long; bring snacks, water and something warm for the boat ride home.
• A good underwater camera or phone pouch is worth it here.