Traditional Cisterns of Naxos Island

Apano Kastro was built in the middle 13th century AD with the purpose to control the agricultural land of central Naxos and to provide a connection point between the harbour at the west and the villages of the interior. It consisted in an outer fortification and the main fortress. Only parts of the wall of the outer fortification are preserved, as well as a horseshoe-shaped barbican which was probably created for the defense of a possible entrance gate. Within the outer perimeter a few traces of houses have been found. On the southwest slope stand the remnants of an ancient wall made of large, evenly cut rectangular blocks, dating probably from the classical Greek period.   

The main castle covers the mountain plateau, enclosing an area with a length of 120 m and a maximum width of 50 m. The surrounding wall consists mainly of straight, right- angle turn lines, while on the north side there is a certain section with an outward-curved form. Within the castle there are the remnants of various separate buildings. There is one construction that is believed to have been a church and a 2 m high wall consisting of a sequence of round arches, running parallel to the north enclosure wall. Further to the east, there is a section of a former building with a length of 20 m and unknown width. It is believed to have been the Palace, of which only the north wall and the northwest and northeast corners are still preserved.

Lastly, inside the castle there are a few cisterns covered with barrel-vaulted roofs.