The island measures north-south and east-west, and has an area of . It is densely wooded and very mountainous and is marked by ridges and numerous deep ravines lead to a steep, rugged coast on the east side of the island off which are tremendous depths. The coastal cliffs are up to high. The south, west and north sides of the island have sandy strips of beach which extend offshore in places. The highest peak, Cerro de Los Inocentes, rises to in the southwest part of Alejandro Selkirk Island, where there is also a prominent rock with a hole through it.