thermal springs in italy

I don't know what Rick says, but Ischia (close to Naples) is well-known for them.

I, also, don't know what Rick says, but Tuscany is well-known for them, too. Any town with "Terme" as part of its name, as well as a host of others.

I too have no clue what Rick says but what part of Italy are you going to? There are plenty in Tuscany, around Rome, and many more places, some free, some part of spas. Differing water temps too!

Many mountains on the Appenines are actually dormant volcanoes. Nearly all natural lakes in central Italy are inside calderas of volcanoes. So there is a lot of volcanic activity underground in Italy (that's why the country is also so seismically active). As it is well known, the Romans loved their thermal baths, to the point that the ancient roads they built had to pass through them.

I can't think of a region that doesn't have them. Tuscany has a lot. Just Google TERME IN.....(fill name of region) and you will get several hits. This is what I got by entering TERME in Toscana:
http://www.gogoterme.com/le-terme-piu-belle-della-toscana.html

My grandfathers village, Poretta Terme has them. Outside of Bologna in the mountains. A small village but several spas located there.