The ruined fortress Belvedere or Rizokastro, the seat of the homonymous Castellana during the Venetian occupation, is located on the hill Kastellos northwest of the village Kastelliana, where in ancient times the city of Priansos was sited. Inside the fortress there are the ruins of the Early Christian Basilica of Priansos with a mosaic floor, as well as six temples. The three of them, including the domed church of Saint George at the peak, are completely ruined. The surviving churches are Saint Anastasia, Kato Panagia and Pano Panagia.
The church of the Dormition of the Virgin Mary or Pano Panagia is located in the northeast part of the castle and bears very ruined frescoes of 1467 painted by Georgios Pelegris. The painter is probably the same with the homonymous painter who worked in Chandakas (today's Heraklion) from 1456-1487 and collaborated with other well-known painters of the time, such as Andreas Ritzos. Among the scenes we can discern Abraham's Sacrifice and Jacob's Dream.