PAD-US—National inventory of protected areas
The Gap Analysis Project produces data and tools that help meet critical national challenges such as biodiversity conservation, renewable energy development, climate change adaptation, and infrastructure investment. The Protected Areas Database of the United States (PAD-US) is the official inventory of public parks and other protected open space. Consisting of more than 7 billion acres in 436,000 land and marine units, the spatial data in PAD–US include areas managed by greater than 30,000 agencies and nonprofit organizations.