Nestled in Wolverine Canyon about 12 east of Firth, ID lies RPM Wall. The climbing is on bobmber limestone that varies from slightly slabby, thin and hard to read to gently overhung section – so mainly face climbing.

Development began in 2004 and has so far produced 9 sport routes, but plans for at least 5 more are in the works.

The wall is a great place to beat the summer sun as it hardly sees any sun at all and is secluded from the road below.

Ratings are mainly .11-.12 and are highly suggestive due to lack of traffic as of summer of 2007. Check this place out if you're in the area.

Head east from Firth, ID along Wolverine Canyon Rd. Once in the canyon, continue on the dirt road for about 2 mi. until you see 40 Horse Cave high up to the left, park here. Across the road from the cave is a shaded gully that ascends the hillside. It's pretty obvious from there where the routes lie.