Grjotagja

A small set of caves with a hot pool of water in them; basically your own private swimming pool (assuming it's cooled down enough and there aren't any passing tours...). However, a tour guide that popped in when we were there had said the rocks that we were sitting on had fallen from the roof last winter - and we were in earthquake territory with the eruption happening nearby(ish). Added a certain frisson to the procedure of taking the photos :)