Snorkeling Koh Lanta: 4 Islands & Emerald Cave by Longtail Boat

The Emerald Cave requires an 80-meter swim through the mountain to reach the lagoon inside.

A full-day snorkeling tour from Koh Lanta by traditional longtail boat visits four islands: Koh Chuak and Koh Maa for reef snorkeling, Koh Ngai for lunch and beach time, and Koh Mook for the Emerald Cave, where you swim through the cave passage to an emerald pool surrounded by steep cliffs. An English-speaking guide, snorkeling gear and hotel transfer are included.

Step-by-step itinerary

Explore 4 Islands by Longtail Boat

• Meet crew at Saladan Pier office
• Boat ride to Koh Chueak
• Snorkel at Koh Chueak
• Visit Koh Mook island
• Swim through Emerald Cave
• Lunch on Koh Ngai beach
• Snorkel and feed fish at Koh Maa
• Return boat trip to Koh Lanta
• Transfer back to hotel

The experience

The day starts with pickup from your hotel on Koh Lanta and a 45-minute cruise by longtail boat to Koh Chuak, a small karst islet with sea caves and sandy beaches. The water here is clear enough to see the reef, and you'll snorkel in open water before moving on. About an hour later you arrive at Koh Mook, the largest island on the route and home to the Emerald Cave. The cave entrance sits on the western side and is only accessible at low tide. Once inside, you swim roughly 80 meters through the passage to emerge onto a white beach with an emerald pool, the water so clear and the cliffs so steep that the space feels sealed off from the rest of the world.

After the cave, the boat heads to Koh Ngai for a Thai buffet lunch on the beach: steamed rice, fried vegetables, Massaman curry with chicken and seasonal fruit. The island itself is mountainous and forested, with clear water and coral reefs nearby. You have time to walk the white sand beach or snorkel again if you choose. The final stop is Koh Maa, where the second snorkeling session takes place. The reef here is thick with fish, and you can feed them with bread or bananas if you want. Thousands of giant bats also roost in the trees. The return to Koh Lanta takes about an hour, with arrival at the pier in the old town around 3:30 p.m. and transfer back to your hotel.

A professional guide who speaks English leads the group and handles the boat. Life jackets, snorkeling equipment, drinking water, soft drinks and seasonal fruit are provided. The minimum group size is 10 people, and the schedule can shift if weather or sea conditions change. You can choose to meet at Lanta Old Town Pier or arrange hotel pickup on Koh Lanta.

What’s included

• Professional English-speaking guide and traditional longtail boat.
• snorkeling equipment and life jackets.
• basic accident insurance.
• Thai buffet lunch on the beach at Koh Ngai with rice, curry, vegetables and seasonal fruit.
• drinking water, soft drinks and seasonal fruit throughout the day.
• hotel round-trip transfer on Koh Lanta.

Options for this experience

2 options

Pickup from hotels on Koh LantaGuide in English or Thai · 09:00Pickup is included from your hotel on Koh Lanta if it is near the main road, covering Kantiang Bay, Klong Nin Beach, Klong Khong, Long Beach, Pra Ae, Klong Dao and Kow Kwang Beach. You will receive the exact pick-up time by email after making your booking.

Meeting point: Lanta Old Town PierGuide in English or Thai · 09:00Please arrive at Lanta Old Town Pier at least 30 minutes before the scheduled departure.

You pick the guide language when booking.

You'll see the exact price of each option when you check availability.See dates and prices

Before you book

Days and timesEvery dayDeparts at 09:00

AgesAdult (12 and older) · Child (4 to 11 years) · Infant (2 to 3 years): free

GroupUp to 25

Live guideEnglish and Thai

Meeting point and pickupHotel pickup is optional; you can also go straight to the meeting point. Ends back at the starting point.You can choose from 7 pickup points.

Cancellation and refundsFree cancellation up to 24 h before the start. After that, no refund.It may be canceled due to bad weather or if the minimum number of travelers isn't reached. If that happens, you're offered another date or a refund.

Prices and times updated today

Good to know

Low physical effortNot recommended during pregnancyNot recommended with heart problemsNot recommended with back problemsInfants must sit on laps

Operated by Trip Store Krabi

Is this one for you?Choose hotel pickup if you want to avoid the trip to Lanta Old Town Pier. Otherwise, meet the boat at the pier near the old town. The full-day schedule and group size of at least 10 people mean the pace is set by the boat's itinerary, not by your preferences, but the fixed route is what fits four islands, two snorkeling reefs and the Emerald Cave into a single departure.

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Top questions

What languages is the tour guided in?

Live guide in English and Thai.

Can children come?

Yes. Ticket types: Child (4 to 11 years); Infant (2 to 3 years): free.

What happens if it rains?

It may be canceled due to bad weather. If that happens, you're offered another date or a refund. Free cancellation up to 24 h before the start.

What is the Emerald Cave like when you get there?

Emerald Cave (Tham Morakot) on Koh Mook is a limestone cavern that winds about 80 meters through the mountain. You swim the passage to reach a hidden lagoon on the far side, a white beach surrounded by steep cliffs and enclosed by the rock walls. The water in the lagoon is so clear it appears emerald-colored. Access depends on low tide, so the cave is not always open.

How much snorkeling time do you actually get on this tour?

You snorkel at two separate reef sites: Koh Chuak on the way out, and Koh Maa on the return. Both are open-water reefs with fish and coral. The Emerald Cave swim is not a snorkeling stop but a passage swim through the cave itself. Time at each reef depends on the group and conditions, but the day is built around snorkeling as the main activity.

Is the swim through Emerald Cave difficult?

The swim through the cave is 80 meters in calm, enclosed water. It is not a dive. You stay on the surface and swim at your own pace. The cave is only open at low tide, and the passage is wide enough for swimmers to move through without crowding. The tour is suitable for all fitness levels, though it is not recommended for travelers with spinal injuries or poor cardiovascular health.

What happens if the weather is bad?

The tour program is subject to change due to weather and sea conditions. If conditions make the islands unsafe to visit or the Emerald Cave inaccessible (usually because of high tide), the operator will adjust the itinerary or reschedule. A minimum of 10 people is required to run the tour.

Does the price include everything, or are there extra fees?

The tour includes the guide, boat, snorkeling equipment, life jackets, lunch, water and fruit. Entrance to Hat Chao Mai National Park costs 200 THB per adult and 100 THB per child and is paid separately. Gratuities are not included.