Oso’s DH

Double-black slab rolls off Medaris, straight down to town

Oso’s DH drops off the south face of Medaris straight toward town, losing 472 feet in under half a mile. The tread hangs on a shale slope with real exposure, and the features are the native rock: long sandstone slab rolls, flagstone-armored steps, dry-stacked walls holding the bench where the hillside won’t. The double-black sign at the entrance means what it says. Line choice is committed once you’re on a slab, and the runout is loose. What you get in exchange is the best view on the town side, the whole Colorado River corridor and I-70 laid out below, with New Castle’s lights coming on if you time an evening lap. Mule deer work this face at dusk; give them room.

It’s downhill-only, managed by the Town of New Castle, so climb to it on the Medaris side and drop in from the top. This is a look-before-you-leap trail: every roll goes, but a couple are steeper than they photograph, and a first-run walk-through saves skin. The shale turns greasy fast after rain or snowmelt; the face is south-facing, so it dries early in spring and bakes in July. Advanced riders only. Everyone else has friendlier ways down the mountain.

The start is an open ridge crest with a near-360 — the Colorado River S-curve, I-70, and the rail line straight below — and the trail bottoms out on a hand-built rock staircase dropping toward the town streets. The signs are blunt: double-black, downhill bikers only, no uphill traffic, and a “Hazards Ahead / Trail Closed” placard goes up in winter. Mule deer work the face at dusk, and locals run festive night laps with string-lit wheels above the glowing town. Foot traffic does happen up top despite the bikes-only signage, so stay sharp on the blind rollovers.

More on this trail: View on MTB Project → (original description contributed by community members on MTB Project)