Porto Santo Island is a Portuguese island 43 km northeast of Madeira Island in the North Atlantic Ocean. It is the northernmost and the easternmost island of the Madeira Archipelago. The municipality has no land boundaries and is encircled by the Atlantic Ocean. Administratively, it is part of the Autonomous Region of Madeira. The length of the island is about 11 km and width is about 6 km. The population in 2001 was 4,474 with a density of 106.1/km².