Bunch of warm pools next to the highway.
In very close proximity to the “beauty baths” there is another set of free outdoor pools with changing room and picnic table, without so much beauty around at the same 35ºC water temperature.
Kouniavitis, Kamena Vourla, Greece: Nothing wrong with it, but I would probably choose the nearby "Καλλυντικές πηγές" if i was in the mood for a lukewarm bath next to the highway. Otherwise just go straight to Θερμοπύλες. – bert