Thermopylae was a disappointment in a way because it's not well looked after, at least not when I was there in 2013 and 2015. It's not what I expected because it's not near the ocean which is miles away! You can smell the sulphur springs which are across the highway from the tourist center but that area was run down in appearance. The hot springs are easy to get to by bike and I actually saw a guy bathing in it although I found the water too hot for me.