Cabo Blanco Absolute Natural Reserve, Nature reserve at the southern tip of Nicoya Peninsula, Costa Rica

Cabo Blanco Absolute Natural Reserve covers 1,172 hectares of land and 1,790 hectares of sea at the southern tip of the Nicoya Peninsula, in Cóbano, Puntarenas. Its rocky platform ends in deep cliffs above two wide white-sand beaches, Cabo Blanco and Balsitas, and 1,600 m offshore stands Cabo Blanco Island, a bare rock 600 m long and 150 m wide. The land holds both evergreen humid-forest trees and dry-forest species that lose their leaves in summer.

Swedish couple Nils Olof Wessberg and Karen Mogensen arrived in Costa Rica in 1955 and settled on the Nicoya Peninsula. After finding Cabo Blanco's forests amid cleared pasture, they bought 1,250 hectares in 1963 and created Costa Rica's first protected area, the model for its national conservation system. Wessberg was murdered in 1975 while campaigning to protect the Osa Peninsula.

The reserve's name comes from the guano that coats Cabo Blanco island, which looks whitish from a distance. Nils Olof Wessberg and Karen Mogensen, who arrived from Europe in 1955, bought 1,250 hectares here in 1963; Wessberg was murdered in 1975 while campaigning for the Osa Peninsula, and the couple is buried at the Nicolás Wessberg Natural Reserve, their original farm near Montezuma.

The reserve lies at the southern tip of the Nicoya Peninsula, reached from the Montezuma-Cabuya and Mal País area. Trails lead through both evergreen and deciduous forest, and the narrow, dangerous path up Cabo Blanco island was built long ago to service two lighthouses, the last abandoned around the 1980s. The rainy season runs from May to November, the dry season from December to April.

The white colour that gave Cabo Blanco its name comes from the guano of seabirds, which covers the rocky islet of Isla Cabo Blanco almost entirely year-round, 1,600 metres offshore. The islet is about 600 metres long and 150 metres wide, has no vegetation, and holds the remains of a lighthouse abandoned around the 1980s.