Koh Rok and Koh Haa are the islands snorkellers mean when they say the Andaman Sea is better than the postcards suggest. They sit well south of Ao Nang, in the marine park off Ko Lanta, and reaching them is a real commitment. The day trip from Krabi starts early with hotel pickup, usually in the dark or soon after, followed by a transfer to the pier and a speedboat run that takes the best part of two hours each way, and it returns in the late afternoon. What you get for the effort is some of the clearest water in southern Thailand. Koh Rok is a pair of islands, Rok Nai and Rok Nok, separated by a narrow channel and fringed by a coral shelf that starts a few metres from a bright white beach, so you can wade in with a mask and be among reef fish within a minute. Koh Haa, whose name means five, is a cluster of limestone islets with a sheltered lagoon, steep rock walls and a cave that you can swim into on calm days. It is loved for the colour of its water and the number of fish around the rocks. The tour we link is a full-day snorkelling trip from Krabi. Trips like this normally include snorkelling gear, lunch and drinks, and the national park fee is usually collected in cash on the day, so confirm what is covered when you book. Stops, timings and the order of the islands change with the sea conditions and the crew makes the call, so treat the itinerary as a plan rather than a promise.
What the day is like
Expect to spend more time on the boat than on any other tour in this guide, so choose it when snorkelling is the point rather than the scenery from the deck. The speedboat ride can be bumpy in the morning, particularly if the wind is up, so sit towards the middle or back of the boat and take a motion-sickness remedy beforehand if you are prone to it.
You will normally snorkel at two or three sites, with a beach stop on Koh Rok for lunch, shade and a rest. Reef fish are abundant, from parrotfish and butterflyfish to schools of small silvery fish that swirl around the rocks at Koh Haa, and sea turtles are sometimes seen, though no operator can promise them.
Season and sea conditions
These islands are part of a national park that closes for the rainy months, so there are no trips in the green season. The tours generally run through the dry season, from roughly November to April and sometimes into early May. Even within that window, a rough day can shorten the programme or switch the route to Phi Phi or the Four Islands instead, so book a rate with flexible cancellation and ask what the operator does if the far islands are not safe to reach.
Visibility is best in the calm months from December to March, and weekdays are quieter than weekends.
Practical advice
Bring a rash guard or long-sleeved top, reef-safe sunscreen, a hat, a dry bag, a waterproof camera and cash for the park fee. Life jackets are normally available for weaker swimmers, but this is a long day in open water and the swell can pick up, so be honest about your confidence. Children who swim well can enjoy it, but the early start and the length of the journey make it a stretch for toddlers.
If you only have time for one snorkelling day, Hong Island is closer and shorter, and Phi Phi is more famous, while Rok and Haa are the pick for clear water and fewer boats. Plan a lazy morning afterwards, because the sun and the sea are tiring.
What to expect
The experience
A full-day speedboat trip from Ao Nang or Krabi Town with hotel pickup, snorkelling at Koh Rok and Koh Haa, a beach lunch and a late-afternoon return.
Best time
December to March for calm seas and the clearest water; trips do not run in the rainy months when the park is closed.
How long
Ten to eleven hours door to door, including roughly two hours each way on the boat.
Tips
Take a motion-sickness remedy, carry cash for the park fee, wear a rash guard and confirm the cancellation terms for rough-weather days.
Quick picks
- Best for
- Keen snorkellers who want clear water and healthy reef and do not mind a very long day.
- Families
- Fine for confident older swimmers; the early start, bumpy ride and length of the day are hard for toddlers.
- Couples
- A beach with few other people and clear water make it a memorable day, if the sea is kind.
- Pair with
- A slow morning on Railay Beach, a sunset cruise or a Thai cooking class the next day.
- Time needed
- A full day, with pickup before sunrise in many cases.
Good questions
How far are Koh Rok and Koh Haa from Krabi?+
They are south of Ko Lanta, so the speedboat run is long, normally close to two hours each way from the mainland piers. That is why the day starts so early.
When can I go to Koh Rok?+
The trips run in the dry season, broadly November to April and sometimes early May. The national park closes in the rainy months, so there are no tours then.
Is the national park fee included?+
It is usually collected in cash on the day rather than in the ticket price. Confirm this with the operator and carry some baht.
Is it better than the Phi Phi Islands?+
It is quieter and the water is often clearer, with more of the day spent in the water. Phi Phi has more famous scenery and a shorter ride, so many visitors do both on different days.
Can children or non-swimmers join?+
Children who swim confidently can enjoy it, and life jackets are provided for weaker swimmers. Because of the long boat ride, it suits older children better than very young ones.
