The best day trips from Koh Lanta, and who each one suits

Most boats leaving Koh Lanta go to one of three places: the Trang islands to the south-east, the national park islands due south, or Phi Phi to the north. They are genuinely different days out, and the brochures make them sound identical.

Here is what each one actually involves, and the honest answer to which suits which kind of group.

Four Islands and the Emerald Cave

The classic. You work south-east to a string of small islands — Koh Ngai, Koh Maa, Koh Kradan and Koh Mook — with the centrepiece being Tham Morakot, the Emerald Cave.

The cave is the bit people remember. You swim roughly 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 sky above it. There is no other way in. It is not physically hard, but it is dark and enclosed, and if that idea bothers you, it is fine to stay on the boat.

This trip runs both ways. On a traditional longtail it is the slowest and cheapest island day we run, at 1,000 THB, and it departs from Lanta Old Town. By speedboat it costs more but the travelling time turns into water time — the same four islands with two and a half hours on Koh Kradan rather than a rushed stop.

Koh Rok and Koh Haa

If you ask local people where the water is clearest, these are the two names you get. They sit far enough offshore that visibility regularly runs past twenty metres, and no road has ever been built near the coral.

Koh Rok is a pair of twin islands with a channel of white sand between them, and it is where you eat — a Thai buffet on the beach with the whole afternoon to swim off it. Koh Haa means "five islands": five limestone outcrops around a sheltered inner lagoon, and it is the last and best snorkel of the day.

Getting to both in one day needs a speedboat. It is a longer, faster, saltier day than the longtail trip and it is worth it for the water.

Phi Phi and Bamboo Island

Phi Phi sits an hour north of Lanta. Going from here rather than from Phuket means arriving at Maya Bay from the quieter side, usually ahead of the bigger fleets.

The morning takes in Pileh Lagoon — a flooded canyon of green water walled in by cliffs — the painted Viking Cave, and Monkey Beach on Phi Phi Don. Lunch is on Bamboo Island, a low sandbar ringed by shallow water you can snorkel straight off the beach.

A word about the monkeys: we do not feed them and we ask you not to either. They are wild, they bite when crowded, and a fed troop stops foraging. Watch them from the water and from a few metres back on the sand.

Longtail or speedboat?

This matters more than which islands you pick.

A longtail is a traditional wooden boat with an exposed engine. It is slower, louder in a friendly way, sits low in the water and carries fewer people. You feel like you are on a boat rather than in one. It is the better choice if you are not in a hurry, if you want fewer people at each stop, or if you get uneasy at speed.

A speedboat gets you further for the same day. That is the entire argument, and it is a strong one if you want Koh Rok or Phi Phi, which are simply too far for a comfortable longtail day. The trade-off is a harder ride in any chop and more people at each stop.

What is included, and what is not

Our trips include hotel pickup and drop-off, mask, snorkel and fins, a life jacket, lunch and drinking water, an English-speaking guide in the water with you, and insurance.

The national park fee is not included, because it is a government charge collected on the day rather than something we set. It differs by destination: the Trang islands sit in Hat Chao Mai national park and charge less than Mu Ko Lanta and the Phi Phi park. The exact figure for your trip is listed on that trip page.

Picking one

If it is your first time and you want the famous thing, take the Four Islands and swim the Emerald Cave.

If you care most about the snorkelling itself, take Koh Rok and Koh Haa.

If you want the postcard, take Phi Phi.

If you are nervous in the water, or travelling with small children, or simply want a slow day, take a longtail rather than a speedboat, and tell us before you book — the pace of the day changes to suit.

Weather, and when not to go

The Andaman has a season. Roughly November to April is the settled window with the clearest water. Through the monsoon months the sea state decides, day by day, and the far offshore trips are the first to become unpleasant.

We would rather tell you to wait a day than sell you a bad one, and if the sea is not safe we cancel and refund or move you. If you want to know what the water is actually doing this week, message us — we are out on it most days.