Paleokastro is located on the east side of the island, between Agia Theodoti and Psathi. Built on the top of a hill, it offers endless views to Paros, Naxos, Amorgos and the Small Cyclades. It is probably a Byzantine castle, from which part of the fortress and the walls are preserved. The picturesque church of Panagia Paleokastritsa is built inside the walls.