[2] The park is named after the Três Picos (Three Peaks) mountains, which reach 2,316 metres (7,598 ft) in altitude, and are considered to be the center of the Serra do Mar range.

[3] The state park is the largest in Rio de Janeiro, and preserves a large portion of Atlantic Forest in excellent condition.

It is home to endangered species such as hawks and cougar (Puma concolor) that require large areas of preserved environment within which to find their prey.

[5] The objectives are to ensure preservation of remnants of the Atlantic Forest in the portion of the Serra do Mar in Rio de Janeiro, to recover degraded areas, to preserve rare, endemic and endangered species of native fauna and flora, to integrate with the central Atlantic Forest corridor in the state, to maintain springs and water bodies that supply the cities, and to encourage recreation, environmental education and scientific research where compatible with the other goals.

[7] It was expanded by state decree 41990 of 12 August 2009 with the addition of 12,441 hectares (30,740 acres) in the municipalities of Cachoeiras de Macacu, Nova Friburgo and Silva Jardim.