Kastro, the village that is its own wall

People have lived on this rock without a break since antiquity. The ancient town had its acropolis on the north side of the hill, walled in local white marble for about 260 m, probably after the Samians sacked the island in 525 BC. A British excavation in 1937–39, under the ruined house of the medieval lords, found offerings from 700–550 BC thrown into a pit when a new temple was built.

The village you walk through began in the 14th century under Januli da Corogna, who seized Sifnos in 1307 and made himself its lord. An inscription of 1365 with his name survives in the ruins of his house, the Despotiko, on the old central square. At first the fortress measured only about 100 by 40 m. Row after row of houses was added outside it, each new ring becoming the new wall, and by the early 17th century around 5,000 people lived on the rock.

The outer houses are three storeys high with few windows, most only about 30 m² inside, often with one flat reached from the lane and another up a wooden stair. There were six gateways into the village, each a covered passage called a lotzia; the main one runs about 7 m through the houses. Walk through one and you can still feel how the place was meant to be defended.

Today about 120 people live here all year. In the evening the lanes are quiet, the wine bar fills, and the sea below goes from blue to black. The museum, open since 1986 in the medieval core, keeps sculpture, pottery and coins of the ancient city.