Wild Willy's Hot Springs

Wild Willy's, also called Crowley Hot Springs, sits on open sagebrush flats in the Long Valley Caldera east of Mammoth Lakes, with the Sierra crest lined up behind it. From US-395, turn onto Benton Crossing Road at the small green church, drive about three miles past the cattle guards, then follow a dirt road roughly a mile and a half to the parking lot. A quarter-mile wooden boardwalk protects the fragile ground between the lot and the springs.

The main attraction is a deep, heart-shaped pool, the hottest of the group and set apart by a pile of rocks; beyond it the water spreads into a creek-like run of pools with room for small groups. Temperatures sit between about 95 and 105°F, and the springs together hold around 30 people. It is free and open year-round, though snow can make the dirt road impassable.

Clothing is optional by custom, so keep cameras pointed away from other bathers. Leave no trace: there are no bins, fires are not allowed at the lot, and vehicles must stay on the road. Darker swimsuits hide the mineral staining if you wear one.

The downside: this is the best-known soak in the area, the lot fills on weekends, and people occupy the heart pool even before dawn.