When I learnt that there was an underground mountain lake in Turkmenistan, I made it my goal to visit it in the short time we were in this strange country.
You essentially enter a cave at the foot of a mountain (it seemed more like a small hill), descend 65m underground down some very old and dodgy wooden stairs, somehow change your clothes in the dark, and then swim into the sulphurous pool that was naturally heated to 36C which contained all kinds of minerals that are said to be good for your body.
The entrance fee of 15usd was appalling considering how basic the conditions of the single amenity there was, the changing room. Then again, how many can say they’ve been to the only underground mountain lake in Central Asia?