Nea Kameni (or "volcano" for the locals) is considered to be the youngest island in the Mediterranean. Having been characterized a natural geological park, it is included in the NATURA program.
Visitors can walk almost every part of it, see the volcano's crater and enjoy a once in a lifetime experience.
Next to the Nea Kameni is the (smaller) Old Kameni. Here you have the opportunity to bathe in the hot springs, which have a temperature of 5 degrees above that of the sea and are rich in sulfur, due to the volcano. You can also try the healing mud! How thrilling is that?
You can get to Old & New Kameni with a boat from Gialo in Fira, Athinios and Ammoudi in Oia.