The park covers an area of 1,338 hectares[1] and is centered on Mount Balbalasang in the barangay of the same name near the provincial border with Abra.

Dubbed the "green heart of the Cordillera",[2] the park is representative of the rich biodiversity and landscape of this mountain region with some of the most intact pine forests and richly endemic flora and fauna.

Mount Sapocoy is the highest peak at 2,456 m. It is located at the western boundary of the park overlooking the Ilocos and Cagayan Valley.

An important center for biodiversity conservation, the park is home to 89 species of birds, of which 39 are endemic to the Philippines and 2 of them can only be found in Luzon, the Isabela oriole and flame-breasted fruit dove.

The park has been designated an Important Bird Area (IBA) by BirdLife International because it supports a significant population of chestnut-faced babblers.