The whole island, apart from the village and a few patches of farmland, lies within the Juan Fernandez Archipelago National Park, a UNESCO Biosphere Reserve managed by CONAF. The park protects an extraordinary collection of endemic species: more than 200 plants found nowhere else, a colony of Juan Fernandez fur seals, and the tiny Juan Fernandez firecrown hummingbird.
Entry to most trails is free but you should sign in at the CONAF office in San Juan Bautista, both for safety and because rangers can tell you which paths are open. Native forest, basalt sea cliffs, and the open ocean view from any ridge are the rewards.