The Venetian Castle of Assos was built in the 16th century by the Venetians to protect the village from pirate attacks and the remaining parts include a vivid Venetian fortification identity and the Venetian Lion of Saint Mark over the gates. Within the ruins, you will find the small church of Agios Markos and the house of the Venetian High Commissioner. A little lower down the hill there is another chapel dedicated to Prophet Elias, which also contains a beautiful wooden carved iconostasis. The strategic location of the Castle allowed supervising the whole sea area and from there you can get a beautiful view of the bay. Till 1956, the Castle of Assos was used as a place for political prisoners, who lived there and cultivated vineyards.