🔄 Updated 21 Jun 2026
Koh Khai sits inside Tarutao National Park, out in the sea between Koh Tarutao and Koh Adang, roughly 25 km west of Pak Bara pier. It's a small island with no accommodation and no facilities, so it's not somewhere to stay the night — it's a stop along the way where nearly every tour boat pauses for half an hour to an hour so you can stroll, take photos, and get in the water.
What makes Koh Khai memorable is the natural stone arch reaching out from the beach — a rock that curves into a ring like a doorway, carved over a long time by wind and waves. It's the image you'll see on Satun's tourism posters and emblems, and almost everyone who arrives walks over to stand under it for a keepsake photo.
The stone arch — symbol of Tarutao and Satun
The stone arch is the heart of Koh Khai — a natural rock formation that curves into a ring like a gateway, sitting at the end of the white-sand beach. At low tide you can walk right under it easily, and it's the most popular photo spot on the island, framed by clear blue sea and sky. The shots come out looking great with barely any editing, and plenty of people come to this island specifically to photograph themselves with the arch.
Beyond being a photo spot, the stone arch carries a local belief passed down over the years: any couple who hold hands and walk through it together will find lasting love and stay together for the long haul. Because of that, the province ran beach weddings and marriage-registration events at Koh Khai on Valentine's Day for several years, turning this little island into a destination for couples too.
Getting a good photo of the stone arch
Mornings are easier — the sun isn't harsh yet, the tide is often out so you can walk right under the arch, and the early light is softer than at midday. People cycle through Koh Khai in waves as tour boats arrive, so if the boat that just landed brought a big group, wait a few minutes for everyone to drift into the water and you'll get the arch to yourself. And don't climb on the wet rocks — they're slippery.
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Snorkeling and swimming at Koh Khai
The beach on the west side of Koh Khai is fine white sand, and the shallow water is clear enough to see the sandy bottom — great for an easy swim and snorkel, especially for beginners and kids. There's coral around the island, mostly staghorn, with small fish darting about close to shore. This isn't the densest coral in Tarutao, but the upside is shallow, calm water that's easy to get into during a break from sitting on the boat.
- Shallow water for beginners — the west-facing beach is clear and shallow, so kids and weaker swimmers can get in. Always wear the life jacket your tour provides.
- Staghorn coral — the reef around the island is mostly staghorn coral you can see from the surface. Don't step on it or grab it — it snaps easily and the edges are sharp.
- Sea turtle nesting — Koh Khai is one of the spots where sea turtles come ashore to nest around November. If you're lucky you might spot the traces, but never disturb a nest.
- Limited time on the island — tours usually give you about 30–60 minutes on Koh Khai, enough to photograph the arch and get in the water once before moving on. Plan whether you'll shoot photos or swim first.
Park fees and the closed season
Koh Khai is inside Tarutao National Park, so there's an entry fee: 40 THB for Thai adults and 20 THB for Thai children, 200 THB for foreign adults and 100 THB for foreign children. The ticket covers several islands in the same group, and most tours either include it or take you to pay. During the monsoon, roughly mid-May to mid-October, the park closes the Adang–Rawi island zone and many dive sites to visitors — fewer boats run and the sea gets rough. Check with the park or your tour operator before planning.
How to get to Koh Khai — from Pak Bara and Koh Lipe
There's no scheduled boat that runs straight to Koh Khai alone — to get here you go through an island tour or charter a boat. Most people reach Koh Khai via two main routes: out of Pak Bara pier on the Tarutao–Adang–Rawi tour, or on a snorkeling tour from Koh Lipe that already includes a stop at Koh Khai.
- From Pak Bara (island tour) — Pak Bara pier in La-ngu district, Satun, is the main gateway to the Tarutao islands. There are day trips and multi-day packages running the Tarutao, Koh Khai, Koh Adang, Hin Ngam Beach and Jabang Channel route; some programs stop at Koh Khai on the way to Koh Lipe.
- From Koh Lipe (snorkeling tour) — if you're staying on Koh Lipe, book a longtail snorkeling tour at a shop on the walking street or through your accommodation. Many programs include Koh Khai along with Hin Ngam, Koh Adang, and the Jabang Channel.
- Private boat charter — if you want to set your own schedule or you're a group, charter a longtail or speedboat from Pak Bara. It costs more than a joining a group tour but gives you flexibility on timing and stops.
- On the Pak Bara–Koh Lipe transfer — some speedboat runs between Pak Bara and Koh Lipe stop at Koh Tarutao and Koh Khai for photos along the way, stretching the trip to around 2–2.5 hours.
Tour prices shift with the season, the number of islands, and the operator, but to give you a rough idea: a day trip from Pak Bara covering Koh Khai and other islands in the group usually starts in the low thousands of THB per person, while a half-day snorkeling tour from Koh Lipe that also stops at Koh Khai starts around 600 THB per person and up in high season. Both usually include snorkel gear and life jackets; some include the park fee, some charge it separately — ask clearly before you book.
Pick the tour that matches what you want to see
If you're set on photographing the Koh Khai stone arch in particular, check with the operator that the program actually stops at Koh Khai and gives you enough time ashore to shoot — because some routes focus more on dive sites like the Jabang Channel or Hin Ngam Beach, and may only slow the boat past Koh Khai so you can shoot from the deck. Compare a few programs and read recent reviews before deciding.
Where Koh Khai fits in a tour — sample plans
Because Koh Khai is a stop rather than a main destination, it usually turns up in the middle of an island route. Here's an example of where Koh Khai falls in the two tour formats people pick most often.
Day trip from Pak Bara (Tarutao–Koh Khai–Adang–Hin Ngam)
Half-day snorkeling tour from Koh Lipe (inner zone)
The best time to visit Koh Khai
The Andaman on Satun's side is at its best and easiest to travel from around November to April — calm sea, clear water, good sun, and plenty of tour boats running. That's the best window for stopping at Koh Khai and snorkeling. During the monsoon, roughly mid-May to mid-October, the park closes many spots in the Adang–Rawi group, the sea gets choppy, fewer boats run, and some routes skip Koh Khai altogether — so always check with your tour operator and the park first.
What to know before you go to Koh Khai
- No overnight stays on Koh Khai — there's no accommodation or facilities on the island; it's a stop only. If you want to stay overnight, base yourself on Koh Lipe, Koh Adang, or Koh Tarutao.
- Bring cash for the park fee — have cash ready for the park fee and tour costs. Ask clearly whether your tour includes the park fee or charges it separately, and keep your park ticket to use across islands.
- Respect nature — don't step on or grab the coral, don't take shells or rocks home, don't disturb turtle nests, and carry your trash back to the mainland. A small island's ecosystem is very fragile.
- Sun protection and dry bags — the sea sun is strong, so use waterproof sunscreen and a long-sleeve sun shirt, and pack your phone and camera in a dry bag because spray comes over the boat.
- Seasickness? Bring medicine — the boats run across open sea and can rock when it's choppy. Take seasickness pills before boarding and sit in the middle of the boat where it's steadier.
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