Santo Antão (Portuguese for “Saint Anthony”), or Sontonton in Cape Verdean Creole, is the westernmost and largest of the Barlavento islands of Cape Verde. The nearest main island is São Vicente to the southeast, separated by a channel named Canal de São Vicente. It is the westernmost large island in Cape Verde and the continent of Africa, and the second largest in Cape Verde.
The island, entirely made up of volcanic material. The tallest mountain is Topo de Coroa, reaching a height of 1,979 m. The second tallest is Pico da Cruz at 1,585 m. The island is divided into north and south by a mountain range long considered impenetrable but now crossed by a road. The island’s main town is Ponta do Sol on the north coast, home to the Agostinho Neto Airport, while its ferry port is Porto Novo on the south coast. A part of the island in the southeast has an arid climate, while the northwest receives relatively normal precipitation. Its valleys are suffering heavy erosion.