Island Paros geographic co-ordinates are 37° N. lat, and 25° 10′ E. long. The area is 165 km2 (64 sq mi). Its greatest length from N.E. to S.W. is 13 mi (21 km), and its greatest breadth 10 mi (16 km). The island is of a round, plump-pear shape, formed by a single mountain (724 m (2,375 ft)) sloping evenly down on all sides to a maritime plain, which is broadest on the north-east and south-west sides. The island is composed of marble, though gneiss and mica-schist are to be found in a few places. To the west of Paros lies its smaller sister island Antiparos. At its narrowest, the channel between the two islands is less than 2 km wide. A car-carrying shuttle-ferry operates all day (to and from Pounda, 3 miles south of Parikia). In addition a dozen smaller islets surround Paros. Paros has numerous beaches including Chrissí Aktí (Golden Beach, Greece) near Drios on the east coast, at Pounda, Logaras, Piso Livadi, Naousa Bay, Parikia and Agia Irini. The constant strong wind in the strait between Paros and Naxos makes it a favoured windsurfing location..