🔄 Updated 21 Jun 2026
Coming to Krabi and never getting on a boat means missing the best thing this place has going for it. The main departure points are Ao Nang Beach, Nopparat Thara Beach and Krabi pier. From here it's a 20–45 minute boat ride to islands where the water is clear enough to see the sand on the bottom. There are three main types of tour to choose from: the 4-island tour, the Hong Island tour, and the evening 7-island tour. Each suits a different kind of traveler, so we'll go through them one at a time.
4-island tour — the classic first-timer's trip
The 4-island tour is Krabi's most popular route, looping Poda Island, Chicken Island, Tup & Mor Islands (the Separated Sea), and Phra Nang Cave–Railay. The highlight is the Separated Sea (Talay Waek), a sandbar that surfaces at low tide and links three islands so you can walk across it in the middle of the ocean. The best snorkeling on this route is right off Poda, where the coral sits only about 20 meters from shore, so you'll spot bright fish easily even if you're not a strong swimmer.
- Poda Island — fine white-sand beach, clear water, and a coral reef right off the beach. The easiest and prettiest snorkel spot on this tour.
- Chicken Island (Koh Kai) — the rock shaped like a chicken's head is the photo landmark, and the reef around the island is good for snorkeling.
- Separated Sea (Talay Waek) — the sandbar linking Tup, Mor and Chicken Islands; you can only walk across at low tide, so check the tide table before you book.
- Phra Nang Cave / Railay — a pretty limestone beach for a stroll and photos before you head back.
About the tides
You can only walk across the Separated Sea at low tide. If you want to see the full sandbar, check that day's tide table and pick a boat departure that lines up with low water. Most tour operators can tell you which day and which slot hits low tide just right.
Want more out of Krabi? Book tours & activities
Booking online ahead on Klook or GetYourGuide is usually cheaper than the gate and skips the queue. Pick only the experiences you actually want — prices and availability are shown live on each site.
Hong Island tour — the hidden lagoon and panoramic viewpoint
Hong Island sits inside Than Bok Khorani National Park, about 6 km offshore — a 30–45 minute boat ride from Ao Nang. The draw is the Hong Lagoon, an enclosed sea the boat slips into through a narrow gap in the rocks, where the water is still and emerald green, plus a 360-degree viewpoint you reach by climbing over 400 metal steps. It's a grind, but at the top you get a panoramic view of the sea wrapping around the island, well worth the sweat. Plenty of people say Hong is less crowded and clearer than Phi Phi.
- Hong Lagoon — an enclosed bay ringed by limestone, calm water, great for kayaking and photos.
- 360° viewpoint — 400+ steps, but the view pays off. Wear shoes you can actually walk in.
- Koh Lao Lading / Koh Pak Bia — snorkel stops with clear water and fewer people.
- Hong Island tours come as both longtail and speedboat, and some operators run an evening trip with night snorkeling to see the plankton.
Hong Island park fee
The Than Bok Khorani park fee for Hong Island is 300 THB for foreign adults and 100 THB for children (Thais pay less), cash only, paid on the spot. Most tour prices don't include this, so always carry extra cash.
Evening 7-island tour — sunset and bioluminescent plankton
The 7-island tour leaves in the afternoon, looping Chicken Island, Tup, Mor, Poda, Taming Island and Railay, then closes with the highlight that sets it apart from the rest: after sunset they take you in to swim with bioluminescent plankton that glows blue when the water moves, along with a buffet/barbecue on the boat or on the beach. It's a good pick if you want daytime snorkeling and an evening atmosphere in a single trip.
Now the honest part: the glowing plankton isn't clearly visible every night. It depends on the time of month (darker, moonless nights show it better) and the water conditions — some nights it's faint, some nights there's plenty. If you're going purely for this, set your expectations beforehand. But if you treat it as a bonus on top of an evening tour that already includes the sandbar, snorkeling and sunset, it's a fair deal.
Rough tour prices (updated 2026)
4-island tour, longtail boat (group tour)
The classic route — Poda, Chicken Island, Separated Sea, Railay. Includes hotel transfer in Ao Nang/town, lunch, snorkel gear and life jackets. Best for a tight budget.
4-island tour, speedboat
Same route but a fast boat, so you move between islands quickly and get more time on each island. Good if you get seasick easily or don't want to bake in the sun on a slow boat.
Hong Island tour, longtail boat
The hidden lagoon plus the 360° viewpoint and snorkeling at nearby islands. Fewer people than the 4-island route and a more relaxed vibe.
Hong Island tour, speedboat
Hong Island by fast boat; some packages include lunch on the island. Good if you want to arrive quickly and have plenty of time in the water.
Evening 7-island tour + plankton
Afternoon departure, snorkeling, sunset, buffet/barbecue, and finishing with a swim among the glowing plankton. The evening slot is quieter than the morning one.
Private longtail charter
Book the whole boat, set your own route, pick the islands and the timing. Ideal for families or couples who want to avoid the big group tours.
Prices are rough ranges
The prices above are based on rates seen on tour-booking platforms in early 2026. They move with the season, promotions, and whether the park fee is included. Confirm before you pay whether the park fee is included, because many operators charge it separately on the spot.
Which snorkel spots have the clearest water
Off Poda Island
Coral about 20 meters from the beach, shallow and clear, fish easy to spot. Good for beginners and kids.
Around Chicken Island
Reef ringing the island, clear water, plenty of fish. A favorite stop on both the 4-island and 7-island tours.
Koh Lao Lading (Hong Island zone)
Fewer people and clear water — good if you want to snorkel without the crowds. On the Hong Island route.
Off Phra Nang Cave / Railay
Clear at high tide, good for shallow swimming and photos against the limestone backdrop.
The clearest water in the Krabi sea comes in the dry season, roughly November to April, when the sea is calm and clear and snorkeling is at its best. During the monsoon from May to October the waves run higher, and on some days tours get canceled or reroute. Check the weather forecast several days before you book ahead.
Longtail or speedboat — which should you pick
- Longtail boat — local atmosphere, close to the coast, cheaper, but slower and more exposed to sun and spray. Good if you're not in a hurry and on a budget.
- Speedboat — fast, quick to move between islands, more time on each island, and has a roof. Good for anyone who gets seasick easily, families, or wanting to cover several islands in one day.
- If you're traveling with small kids or older relatives, a speedboat is clearly more comfortable.
- If you want the traditional Krabi-sea feel on a budget, the longtail is the answer.
Before you board
- Bring cash for the park fee (Hong Island is 300 THB per foreign adult), since it's usually not included in the tour price.
- Reef-safe sunscreen, a sun shirt, sunglasses and a hat — the Andaman sun is brutal.
- Wear strap-back sandals or water shoes; there are rocks and sandbars to walk over.
- A waterproof pouch for your phone and wallet — things get wet on the boat.
- If you get seasick easily, take medication 30 minutes before departure and pick a speedboat for a smoother ride.
- Book ahead in high season (Nov–Apr) because slots fill up fast.
Plan your whole Krabi sea trip — hotels, food and where to go
See the Krabi travel guide →