A longtail boat crossing bright turquoise water between jungle-covered limestone islands

Nine seats, one wooden boat, the quiet side of the Andaman.

We are a family crew on Koh Mook, in Trang province. We leave when the tide suits the route, not when the big boats do, so you swim into Emerald Cave with a handful of people instead of a few hundred.

Choose a tour See the photos

Day tours from ฿1,100 per person, lunch and snorkel gear included.

Why we leave at 08:30

The cave tunnel is only swimmable around low water. On a day like this one, the window is 09:00 to 11:30, and the mainland boats arrive at 11:00.

04:28High 2.7 m
10:40Low 0.7 m
16:55High 2.9 m

Sample spring-tide day at Koh Mook. The shaded band is the cave window.

Four days out from Koh Mook

Scroll and the boat sails each route on the chart. Every price is per adult and covers everything on the list. Children aged 4 to 11 pay half.

Sketch chart, not for navigation. Depths in metres at low water. In red: the emerald cave route.

Looking out from inside a dark sea cave onto bright turquoise water

Emerald Cave and three islands

฿1,900 per person

We time the day around low water, so you swim the 80 metre tunnel into the hidden lagoon before the big boats arrive from the mainland.

Duration: 7.5 hours
Leaves: 08:30
Group: 9 at most
Per person: ฿1,900

The day, hour by hour

08:30Leave Koh Mook pier, safety talk on the way round the north cape
09:15Swim into Emerald Cave while the tide is low and the tunnel is empty
10:45Cross to Koh Kradan, snorkel the east reef from the boat
12:30Lunch in the shade on the beach, an hour to do nothing
14:00Koh Chueak: soft corals and a short swim-through for confident swimmers
16:00Back at the pier

Included

Mask, snorkel and fins in your size
Life jacket and a guide in the water with a torch
Lunch on Koh Kradan: massaman or vegetable curry, rice, fruit
Drinking water, iced tea and a dry bag

Runs: November to April.

Reserve seats on this tour

A snorkeller floating over orange sea anemones in clear shallow water

Kradan reef morning

฿1,300 per person

A half day for people who mostly want to be in the water. Two long snorkel stops on the Kradan reef, back in time for lunch on Koh Mook.

Duration: 4.5 hours
Leaves: 08:00
Group: 8 at most
Per person: ฿1,300

The day, hour by hour

08:00Leave Koh Mook pier and run south with the morning calm
08:45First snorkel on the east reef: clownfish, parrotfish, giant clams
10:15Fruit and tea on the boat, short hop to the south point
10:45Second snorkel over the hard coral garden, 2 to 5 metres deep
12:30Back at the pier

Included

Mask, snorkel and fins in your size
Life jacket and a guide in the water
Fresh fruit, drinking water and iced tea
A laminated fish card to tick off what you saw

Runs: All year, weather allowing.

Reserve seats on this tour

A dugong grazing on seagrass on a sandy sea floor

Libong seagrass and dugong watch

฿2,400 per person

A slow day in the shallow channel off Koh Libong, where dugongs graze the seagrass on a rising tide. Engine off, eyes open, no promises: we see them on about two trips in three.

Duration: 8 hours
Leaves: 07:30
Group: 6 at most
Per person: ฿2,400

The day, hour by hour

07:30Leave Koh Mook pier and head south-east across the channel
08:30Land at the north cape of Libong, walk the sandbar at low water
10:00Drift over the seagrass beds with the engine off
12:00Lunch in the village: grilled fish, crab curry, vegetable options
13:30Climb the limestone viewpoint and scan the channel from above
15:30Back at the pier

Included

Binoculars for every pair of guests
Climb to the Batu Bute viewpoint with a village guide
Seafood lunch at a family kitchen in the fishing village
Drinking water, iced tea and a contribution to the seagrass patrol

Runs: All year, weather allowing.

Reserve seats on this tour

The prow of a longtail boat on the water as the sun sets behind it

Sunset round Koh Mook

฿1,100 per person

A full circle of the island under the west cliffs as the light goes orange, then squid fishing with hand lines once the lamps come on.

Duration: 3.5 hours
Leaves: 16:30
Group: 8 at most
Per person: ฿1,100

The day, hour by hour

16:30Leave Koh Mook pier and follow the south shore
17:15Swim stop under the west cliffs, swiftlets coming home overhead
18:10Drift west of the island for the sunset
18:45Lamps on, lines down for squid off the north cape
20:00Back at the pier

Included

One cold drink each and grilled corn from the boat stove
Hand lines and jigs for squid fishing
Light jackets if the breeze picks up
Whatever you catch, grilled before we head home

Runs: All year, weather allowing.

Reserve seats on this tour

Reserve seats

No payment now. You pay in cash or by bank transfer at the pier on the morning. We confirm by 18:00 the evening before, once we have seen the forecast.

One day, six frames

Warm, clear water, cliffs that drop straight into it, and long stretches with no other boat in sight. Keep scrolling.

A turquoise lagoon between two sheer, jungle-covered limestone cliffs under a blue sky — 01 *09:40*Cliffs that drop straight into the lagoon

A snorkeller in a red life vest swimming among small striped reef fish — 02 *10:55*On the reef, the fish come to you

A sea turtle seen from above, swimming over a shallow reef — 03 *11:20*Green turtles, most weeks

Two longtail boats anchored off an empty white-sand beach — 04 *12:30*Lunch, then an hour to do nothing

A wooden longtail boat with garlands on its prow, resting in clear shallow water — 05 *14:10*Garlands and ribbons for Mae Ya Nang

A small boat anchored off a dark shore under an orange sunset, with islands on the horizon — 06 *18:15*Last light on the way home

The seventh frame is yours.

Reserve seats

View from the bench of a wooden longtail boat, over its painted bow, towards jungle-covered cliffs

Longtail boats on a white beach, their tall prows wrapped in coloured ribbons and flower garlands

The boat is called Nong Fai

She is an 11.5 metre longtail, built in 2016 at a yard in Kantang from takhian wood and repainted every October. The three ribbons on her prow are for Mae Ya Nang, the spirit who looks after the boat. We retie them each new season, and that is where the name comes from.

Seats: 9 guests and 2 crew, on cushioned benches under a canvas roof
Safety: 14 life jackets including 4 child sizes, marine radio, first aid kit, oxygen
On board: Boarding ladder, dry box for phones, ice chest, a toilet stop every two hours
Engine: Four-cylinder diesel on the tail, serviced every 200 hours, about 12 knots

Bang Mat, captainBorn on Koh Mook. Fished these channels for 25 years before he took guests, and reads the tide off the rocks.
Fon, guideIn the water with you at every stop. Speaks Thai and English, some German. Trained in first aid and rescue.
Kai, deckhandHandles the anchor and the ladder, cooks on the boat stove, and spots turtles before anyone else.

Before you come

Getting to the boat

On Koh Mook, walk or take a sidecar taxi to the main pier on the east side. We are the green and red boat at the last berth.

From the mainland, we collect you at Kuan Tung Ku pier at 07:45 at no charge. From Trang town, our minivan leaves hotels at 06:45 for ฿300 per person, return.

What to bring

Swimwear on under your clothes, and a towel
Reef-safe sunscreen, a hat, a long-sleeved shirt
฿200 in cash per adult for the national park fee
Seasickness tablets if you need them, taken before boarding

Leave at home: drones, single-use plastic bottles, fish food.

Season and weather

November to April is the dry season: flat mornings, water at 28 to 30 °C, 15 metres of visibility on a good day.

May to October is monsoon. Emerald Cave closes, the other tours run when the forecast is under 15 knots. If we cancel, you move the day or pay nothing.