To visit La Selva, it is necessary to contact the office of the Organization for Tropical Studies in San José. Station Headquarters lie 5 kms. south of Puerto Viejo de Sarapiquí. From the Central Valley 87 kms. via Alajuela-Carrizal- Varablanca- Bajos Chilamate- Puerto Viejo- Station Headquarters, or 73 kms via San José- Tunnel Zurquí- Río Chirripó- Horquetas- Tigre- Station Headquarters.
The National Academy of Sciences of the United States has recognized La Selva Biological Station as one of the four most ideal places in the world for rainforest research. The station is administered by the Organisation of Tropical Studies (O.E.T.) a consortium of American and Costa Rican universities that functions as an ecological education and research center.
The biological center is located on the northern plains near the confluence of the Rivers Sarapiquí and Puerto Viejo. It ranges over 1,534 hectares of primary forest, swamps and abandoned farmland. Over 500 species of birds, 100 species of mammals, thousands of insects, and 2000 species of plants, including 800 species of trees (more than Canada and the United States together), have been identified in this biologically rich area. Its forest provide refuge for the tapir, jaguar, sloth, white nosed coati and white faced capuchin and howler monkeys, among many other species.
The average temperature of 27°C with 4000 mm of annual rainfall causes a feeling of sticky dampness, especially near noon. These hot and humid lands, which can be traversed by means of a network of over 50 kms. of trails, climb through a high altitude passage as far as the continental divide at Braulio Carrillo National Park (2,906 meters above sea level). These passages are especially important for conserving birds and butterflies on high altitude migratory routes and for ensuring the survival of several felines that need vast tracts of land on which to live.