The Castle was built in the 13th century on the hill of Prophitis Ilias, on the northwest edge of the island (today’s Plaka).
Nowadays it is not inhabited, but its visitors can admire a view of incomparable beauty of the entire island bay and of the magic sunset that is worth enjoying when you decide to climb all the way to the top. Also, ascending to the Castle, you will have the chance to see the church of The Assumption of the Virgin Mary or Panaghia Skiniotissa and the church of Panaghia Thalassitra.
This Venetian Castle was not surrounded by walls, as it was the case with most of the Cycladic castles, but it was protected by the houses. Practically, the castle was used to protect the local population against the attacks of pirates (a frequent phenomenon of the era), and also for the control of the ships’ movements in Adamantas bay. On its top, the “Mesa Kastro”, the Tower of the Governor was located, the so called Palace and around the tower there were a few houses. It was established by the first duke of Naxos, Marcus Sanoudos and in the Mesa Kastro there were mainly the residencies of the Duke’s manors and deputies, as well as of other relatives and Franks.