Approximate location — plotted from published sources, not a site visit, and not a guarantee of access.
Utah’s hottest developed geothermal field on the west flank of the Mineral Mountains northeast of Milford — steaming ground, boiling mud pots, sulfur-stained dead zones, and ruins of the early-20th-century Roosevelt Hot Springs Resort beside PacifiCorp’s Blundell geothermal plant. Utah Geological Survey GeoSights interprets magmatic heat, the Negro Mag and Opal Mound faults, and why original soak springs dried after production began; this is a geology stop, not a swimming site.