Bentonite Hills

Bentonite Hills is a broad stretch of rounded, color-banded clay hills along Hartnet Road in Cathedral Valley. It’s on Bureau of Land Management land outside Capitol Reef’s boundary, but it’s part of the park’s Cathedral Valley outing. I’d include them in a day on the loop, not make a separate trip just for the hills. Come for the layered landscape, not a hike: there are no trails through them. For a photo, set the rounded folds against the flat-topped mesas on the horizon so the bands have some scale.

The hills are one stop on a remote 57.6-mile loop that takes about six to eight hours to drive. Hartnet Road requires a high-clearance vehicle; whether four-wheel drive is needed depends on road conditions. The route includes an unbridged Fremont River ford, and high water or wet roads can make it impassable. Check current conditions with the park before setting out, and never cross the ford during high water.

There’s no potable water in Cathedral Valley and cell service is usually poor or absent; help may take hours or days. Treat this as a planned backcountry drive, not a quick detour. The approach to the ford crosses private land, so obey posted no-parking and no-camping signs.

The hills are made of Brushy Basin shale in the Morrison Formation. Jurassic lakes and swamps collected mud, silt, fine sand and volcanic ash here; the ash later altered into bentonite clay. When wet, the clay turns slick and gummy. Repeated wetting and drying leaves the familiar popcorn-like surface.

The surrounding Cathedral Valley took its name in 1945 when Frank Beckwith and Charles Kelly saw cathedral-like forms in the taller formations. Bentonite Hills are a different kind of landscape: lower, rounded slopes shaped by clay rather than those towering sandstone forms.

Footprints and tire tracks can scar the fragile clay for years. Stay on the road and limit walking to firm, previously disturbed ground or wash bottoms; don’t wander across the hills for a closer view. That restraint keeps the banded slopes intact for the next visitor.