The ruins of this medieval city cover the hill behind the Monastery of Aghios Nektarios. This is where the islanders used to take refuge from pirates and invasions for 10 centuries.

Once a small city of 300 churches, some 32 frescoed churches (13th to 17th century) are still preserved. An official is on the site most days and will open chapels usually kept locked, but one can visit the hillside anytime. Crowing the summit are the remnants of a medieval castle.