KEFALOS "in the heart of wilderness" is known for: 
Its microclimate, its dream beaches. Its breath taking views, its water sports and fishing. Its opportunities for walks and hikes and its places moulded by history.
Kefalos & history: The White Rock caveIn Aspri Petra, a cave contains interesting paleontological remnants which show that life on the island began in the Neolithic Age (3rd millennium BC). 
The ruins of the island's first capital In Palatia, the remnants of a theatre and a temple (from the Hellenistic Age) date Astypalaia, the former capital of the Island during Antiquity and all the way back to 366 B.C. 
Other places of interest are the remnants: 
Christian basilica of St. Steven,Two paleochristian basilicas with 3 naves, in Aghios Stephanos (5th -6th century). 
The old monastery of St. John the Baptist  The remnants of its Venetian castle and many more...