Tham Lot

Tham Lot is a tide-dependent sea cave inside Ao Phang Nga National Park in Phang Nga, entered by kayak through a natural limestone tunnel at the base of one of the bay’s karst islands. Entry costs 300 THB for foreigners (60 THB for Thai nationals), the standard national park fee, and the park is open daily 08:00-16:30.

The cave itself is short but atmospheric: a natural passage cuts through the rock, opening into a chamber lined with stalactites and stalagmites built up over thousands of years of mineral deposit. Because the passage sits close to sea level, whether you can get through at all depends entirely on the tide — at high water the gap between the surface and the cave ceiling disappears, so boat operators plan trips around the tide tables rather than a fixed schedule. Most visitors reach it on a day tour departing from Phang Nga town pier, Surakul Pier, or Hin Rom Pier in Takua Thung; the tour boat carries kayaks and switches passengers over once it reaches the cave mouth, so no paddling experience is required to get inside.

Tham Lot rarely appears as a standalone stop. It sits among the limestone islands scattered across Ao Phang Nga, within paddling distance of better-known landmarks like the floating village of Koh Panyi to the north, so most operators fold it into a half- or full-day circuit of the bay rather than a dedicated trip.

Watch out: Tide timing decides everything here — a tour that gets you through the cave mouth at 9 AM might find it sealed shut by 1 PM. Confirm with your operator that the schedule matches the day’s tides rather than a fixed departure time.

Insider Tip: Bring a dry bag. The transfer from tour boat to kayak, and the low, sometimes wet passage through the cave itself, means cameras and phones get splashed more often here than on a standard Phang Nga Bay cruise.

Tham Lot shares its national park fee and boat routes with the wider Ao Phang Nga bay and the floating village of Koh Panyi. It’s usually booked as part of a wider circuit around Koh Yao Noi and the surrounding bay.