The National Geologic Map Database (ngmdb.usgs.gov) is a comprehensive resource developed by the United States Geological Survey (USGS) that provides access to a vast collection of geologic maps covering the United States. The website serves as a central repository for geologic mapping data, offering users tools to search, view, and download maps that detail the geology, structure, and stratigraphy of different regions. The NGMDB supports a wide range of users, from geologists and researchers to educators and land-use planners, providing essential information for understanding the geological features and history of the country. Continuously updated and expanded, the database is a critical resource for scientific research, resource management, and environmental planning.