Emerald Cave is a cave located on the west coast of Ko Muk Island, - The paradise island of Ko Muk and Emerald Cave are part of the Trang Provence, Southern Thailand.
The cave has a narrow 80
m long tunnel. The cave can be entered either by swimming or by using a kayak. It is best to see the cave at mid tide, because at low tide there will be no water, hence no 'emerald' on the beach inside.
Wikipedia https://en.wikipedia.org/wiki/Emerald_Cave_(Thailand)
Address Thailand
Coordinates 7°22'9.193" N 99°17'1.575" E