The lava dome & volcano Profitis Ilias
The lava dome of the volcano Profitis Ilias adjoins directly to the eruption of Rethi volcano. He's probably the same age. The summit of this volcano was home to a medieval sanctuary, where the inhabitants retreated against the pirate raids. Therefore, the other name is also "Kastelli" = "castle". It is easy to get on a trail to this summit, because there is also the small chapel Profitis Ilias.