What sources were used to create the Boundaries, Structures and Transportation layers in The National Map?

Boundaries: Primary sources include the U.S. Census Bureau, Bureau of Land Management (BLM), International Boundary Commission (IBC) for the Canadian boundary, and the International Boundary and Water Commission (IBWC) for the Mexican boundary. Boundaries include city, county, State, Federal lands, provinces, and territories; as well as cadastral data (where applicable), associated with Public Land Survey System (PLSS), and Indian lands.

Structures: Currently included at a national scope are hospitals, law enforcement, fire stations, and other similar essential facilities. This data was developed as part of an ongoing effort between Federal agencies and States. For The National Map, the primary sources for the data are states and volunteers associated with The National Map Corps. The USGS reconciles the collection of structures data with the location and feature names from the Geographic Names Information System, achieving a single baseline of data for State and Federal vector data sources as well as gazetteer applications.

Transportation: Roads are from U.S. Census Bureau's TIGER/Line Shapefile source content with some updates of major roads by the USGS, along with U.S. Forest Service road data over National Forests. Railroads were originally sourced from the Oak Ridge National Laboratory but the Federal Railroad Administration is now responsible for maintaining a national dataset. Airport runways are derived from the Federal Aviation Administration location points, with polygon geometry and locational updates provided by USGS.