The Steam Cave
By far the most popular vent, this appears from the outside like a big
mound with greenery hiding any obvious clues to the real workings going
on within. Inside is a true steam bath operating 24/7 free of utility
bills.
Here you see just the entrance right center and the clothes left
outside by the current occupants.
There is a wooden plank bench that someone put in there and another
piece of plywood that you can prop up as a door to intensify the
experience. You can feel the earth's heat puff at you until you can
take no more and have to surrender. Generally for me it is about 20-30
minutes.