The Protected Areas Database of the United States (PAD-US) is America's official national inventory of protected areas, managed by the USGS Gap Analysis Project (GAP). This dataset represents the Combined layer which integrates all protection types: fee ownership, easements, proclamation boundaries, marine protected areas, and designation areas into a comprehensive national resource.
PAD-US 4.1 combines data from federal, state, local, and private land management agencies to provide a complete picture of conservation lands and waters in the United States, including territories and freely associated states.
U.S. Geological Survey (USGS) Gap Analysis Project (GAP). 2023. Protected Areas Database of the United States (PAD-US) 4.1: U.S. Geological Survey data release. https://doi.org/10.5066/P96WBCHS
Public Domain (U.S. Government Work) - As a work of the U.S. Government, PAD-US is not subject to copyright protection within the United States (17 U.S.C. § 105). International copyright and database rights may apply.
Attribution: When using PAD-US data, please cite the USGS GAP as shown above.
This dataset is available in three cloud-native formats:
Most features (99.997%) are indexed at H3 resolution 10 (~15m² cells). However, 20 features with extremely complex geometries (>800K vertices) are indexed at the coarser H3 resolution 8 (~0.74 km² cells) due to computational constraints. These features include:
All features maintain consistent parent resolution columns (h9, h8, h0) enabling seamless integration during spatial queries.
Overlapping Features: The Combined layer contains overlapping features (fee, easement, designation, marine, proclamation). A single location may be covered by multiple records. When calculating total protected area, use geometric operations to handle overlaps appropriately.
Temporal Coverage: Features span from the 1800s to present. Check Date_Est and Src_Date fields for temporal relevance.
Access vs. Protection: Pub_Access indicates public access rights, not protection status. A highly protected area (GAP 1) may have no public access (XA).
Mixed Resolutions: Most features use H3 resolution 10, but 20 extremely complex features use resolution 8. Both resolutions share common parent columns (h9, h8, h0) for compatibility.
Null Values: Many fields may be NULL where information is not available or not applicable to that protection type.
For questions about PAD-US data content and standards, contact USGS GAP Analysis Project.
For questions about this cloud-native format, contact the Boettiger Lab at UC Berkeley.
This cloud-native version was processed using the cng-datasets tool:
Last updated: February 2026