Pilón Lajas Biosphere Reserve and Communal Lands, Biosphere reserve in La Paz Department, Bolivia.

Pilón Lajas is a protected area covering approximately 400,000 hectares of humid tropical and subtropical forests mixed with Amazonian plains. The Quiquibey River runs through the territory, creating a landscape with distinct forest zones and diverse habitats.

The reserve was officially recognized as a biosphere reserve and indigenous territory in 1992 through government decree. This recognition marked a significant step in securing land rights for the communities living there.

Several indigenous groups live within the reserve and maintain traditional practices adapted to forest life over many generations. Daily routines here center on hunting, fishing, and farming in ways that have existed for centuries.

The reserve lies about 350 km northeast of La Paz and 50 km west of San Borja. The Quiquibey River, over 125 km long, is the main waterway inside the area, and the Beni River marks its drainage outlet. There are no weather stations inside the reserve; rainfall data come from Rurrenabaque records.

The reserve's name comes from two landmarks: the Pilón Lajas hills, where its rivers rise, and the Pilón Lajas range itself. Its headwaters in the Beu, Chepite and Pilón Lajas hills feed five sub-basins draining to the Beni and Mamoré rivers, regulating floods and droughts for communities downstream.