Data base: PAS-US 3.0 Spatial Analysis and Statistics - Data Resource page.

Administered by the U.S. Geological Survey Gap Analysis Project, the Protected Areas Database of the United States (PAD-US) is the nation’s official inventory of public open space and private protected areas. The lands included in PAD-US are assigned conservation status codes that both denote the level of biodiversity preservation and indicate other natural, recreational and cultural uses.