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Full day Longtail boat Bestseller

4 Islands & Emerald Cave

The classic Lanta day out, on a traditional longtail

Koh Ngai, Koh Ma, Koh Chueak and the swim-in Emerald Cave at Koh Mook — a full day at an unhurried longtail pace.

This is the trip most people picture when they think of Koh Lanta. A traditional wooden longtail takes you south-east across calm morning water to a string of small islands, each one a different kind of snorkeling.

The centrepiece is Tham Morakot — the Emerald Cave — on Koh Mook. You swim about eighty metres through a dark limestone tunnel, holding a float line, and come out on a hidden beach ringed by cliffs with a circle of open sky above it. There is no other way in.

The longtail is slower than a speedboat and that is the point: more time in the water, fewer people at each stop, and an engine you can talk over.

Highlights

  • Swim the 80m tunnel into the Emerald Cave
  • Shallow, calm coral gardens at Koh Ma
  • Soft coral and sea turtles around Koh Chueak
  • Thai lunch served on the boat
  • Slow pace — roughly 45 minutes in the water per stop

How the day runs

  1. 08:00

    Hotel pickup

    Minivan collects you from anywhere on Koh Lanta Yai.

  2. 08:45

    Depart the pier

    Safety briefing, gear fitting, and out past the headland.

  3. 10:00

    Koh Chueak & Koh Waen

    Two small rock islands. Soft coral, a good chance of green turtles.

  4. 11:15

    Emerald Cave, Koh Mook

    Swim the tunnel in a small group with your guide and a float line.

  5. 12:30

    Lunch at Koh Ngai

    Thai lunch on the beach or aboard, then free time to swim.

  6. 14:00

    Koh Ma

    The shallowest, calmest coral of the day — good for nervous swimmers.

  7. 14:45

    Sail home

    Fruit and cold water on the way back to shore.

Times are indicative. Sea state, tide and the national park can all shift the running order — your guide will tell you on the morning if anything changes.

What's included

  • Hotel pickup and drop-off on Koh Lanta Yai
  • Mask, snorkel and fins
  • Life jacket and float ring
  • Lunch, seasonal fruit, drinking water and soft drinks
  • Experienced local guide in the water with you
  • Insurance

Not included

  • National park fee — THB 400 adult / THB 200 child, paid on the day
  • Towels
  • Alcoholic drinks

Where this trip goes

Emerald Cave (Tham Morakot) An 80-metre swim through a dark limestone tunnel into a hidden beach with cliffs on every side.
Koh Ngai A long east-facing beach with a fringing reef you can snorkel straight off the sand.
Koh Chueak & Koh Waen Two small rock islands with soft coral, swim-through arches and regular turtle sightings.

Before you book

  • Fitness: Easy–Moderate. Life jackets and float rings are on board and a guide stays with anyone who is not a confident swimmer.
  • Bring: a towel, a rash vest, reef-safe mineral sunscreen, a dry bag, and cash in baht for any national park fee.
  • Weather: if we cancel for sea conditions you get a full refund or a free move to another day.
  • Reef rules: no standing on coral, no touching wildlife, no feeding monkeys, and no sunscreen containing filters banned in Thai marine parks.
Also consider

Other trips you might prefer

Ready to get in the water?

Tell us your dates and how many of you there are. We will tell you honestly which trip fits — and if the weather is against you, we will say that too.

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