Koh Haa (Ko Ha Yai)
A cluster of five uninhabited limestone islets whose sheltered lagoon, walls, swim-throughs and 'the Cathedral' cavern make it the top scuba site within easy reach of Ko Lanta, also good for snorkelling.
- Category
- Diving & Snorkeling
- Entrance fee
- Marine national park fee applies, roughly 400 THB foreign adults as of 2026, usually included in the dive/snorkel tour; confirm locally
- Hours
- Daylight, day-tour dependent; access reduced in the low-season monsoon
- Best time
- Nov-Apr for calm seas and best visibility
- Time needed
- Full-day tour
- Difficulty
- Easy to moderate for snorkelling; scuba sites suit various levels
About Koh Haa (Ko Ha Yai)
Koh Haa is the top scuba site within easy reach of Lanta, and divers rate it highly. It's a cluster of five uninhabited limestone islets, and the draw is a sheltered lagoon plus walls, swim-throughs and 'the Cathedral' cavern. If you dive, this is the day-boat trip to prioritise.
Snorkellers get plenty out of it too, thanks to the calm lagoon, though the real magic is underwater. The scuba sites suit a range of levels, so it's not only for the experienced.
Come in the dry season for calm seas and the best visibility, since access is reduced during the low-season monsoon. The park fee is usually built into the dive or snorkel tour, but confirm locally.
Highlights
- Cluster of five uninhabited limestone islets
- Sheltered lagoon that's good for snorkelling
- Walls, swim-throughs and 'the Cathedral' cavern for divers
- The top scuba site within easy reach of Ko Lanta
Tips
- Prioritise this trip if you dive; the underwater terrain is the highlight
- Come in the dry season for calm seas and best visibility
- Scuba sites suit various levels, so ask operators about beginner options
- The park fee is usually included in the tour, but confirm locally
How to get there
Speedboat dive/snorkel day tour from Saladan pier, roughly 45-60 min (~15-18 km west)