Safety in Thermal Areas
Yellowstone’s thermal features, rare among the earth’s wonders, are extremely fragile. Boardwalks and trails protect you and preserve delicate formations. You must stay on boardwalks and designated trails. Scalding water underlies most of the thin, breakable crust. Pools may be near or above the boiling temperature and can cause severe, possibly even fatal, burns.
Pets are prohibited in thermal areas.
Swimming or bathing in thermal pools or streams, where water flows entirely from a thermal spring or pool, is prohibited. Where swimming is allowed, swim at your own risk. Thermal waters may contain organisms know to cause infections and/or amoebic meningitis, which can quickly be fatal. Obtain more information at any ranger station or visitor center.