Hot springs in the U.S., by the numbers

The list we use is the Thermal Springs List for the United States, compiled by NOAA's geophysical data center from U.S. Geological Survey records and published around 1980. It gives each spring's name, coordinates and the maximum temperature measured at the surface. NOAA has kept it as an archived data set; it was not updated after 1980, so a few springs have changed, been capped for geothermal wells or dried up since. We treat it as a geological record and add checked, current access facts only for places on public land.

Most springs on the list are not visitor sites. Many are on private ranches, inside closed areas, or are small seeps a few degrees warmer than the ground around them. The places with a page on this site are on national forest, BLM, national park or state park land, and each page names the agency office, the trail, the fee and the season, with a link to the agency.