Geographic Names Information System (GNIS) does include caves but the entries are not publicly available. In response to the 1988 National Cave Management Resources Act, Department of the Interior Regulation 43 (CFR Subtitle A, Part 37) forbids the release of information regarding the location of all caves on Federal lands. Currently, GNIS does not distinguish between features on Federal versus non-Federal lands, so all features classified as “cave” are blocked from public access.
Information regarding the names and locations of caves in GNIS can be requested in writing from the Secretary of the Interior. Each request will be analyzed on a case-by-case basis. Mail requests to:
U.S. Department of the Interior, Secretary of the Interior
1849 C Street NW
Washington, D.C. 20240