Afternoon storm risk is the line that matters. Everything else is comfort. In summer, plan to be off the ridge before the build-up starts, not as it starts. Forecast for the summit point, adjusted for its elevation · data from Open-Meteo.
Colorado 13er · East Ridge from Willow Basin
Overview
UN 13,015 is a short climb from the pass between it and UN 13,350, above Willow Basin north of the Maroon Bells. From Maroon Lake, trails take you over Willow Pass and across Willow Basin to within 20 minutes of the summit.
It is Class 2 on small white rubble and talus. New mapping shows it has only 292 feet of prominence, so it no longer counts as a ranked 13er, but it is still a fine summit.
The round trip is about 11.8 miles with about 4,700 feet of gain, including the climb back over Willow Pass. Mileage and gain are our estimates. Most people pair it with UN 13,350.
Plan of the day
Start by
Catch the first shuttle, or be parked by 5:30 a.m. with a reservation.
Turnaround
Be at the pass above Willow Basin by 11 a.m.
Crux
Nothing hard; just the distance.
Route-finding
Easy. Trail to the pass, then walk the ridge west and south to the high point.
From the roundabout on Highway 82 just west of Aspen, take Maroon Creek Road (County Road 13) south toward Aspen Highlands and Maroon Lake. About 4.7 miles in is the entrance station, where you pay a fee.
In summer the road is limited: you need a parking reservation, often made months ahead, or you ride the shuttle bus from the Aspen Highlands lot. Check the White River National Forest website for this year's rules before you go. There is no camping at Maroon Lake. Silver Bar, Silver Bell and Silver Queen campgrounds along the road are small, reservable and usually full.
Trail in the treesRidgeTalus and screeExposed to lightning
The line is elevation, the band underneath is the ground, and the numbered dots match the steps below. Mileage and elevations are approximate.
1
Maroon Lake trailhead 9,600' · 0 mi
Take the Crater Lake Trail (1975) along the lake. Don't get pulled onto the scenic loop around Maroon Lake. Overnight campers must register at the trailhead and carry a bear canister.
2
Crater Lake junction 10,080' · 1.8 mi
Near Crater Lake, turn right (west) on Trail 1978 toward Buckskin Pass. It climbs hard up Minnehaha Gulch.
3
Minnehaha Creek 11,060' · 3 mi
About 3 miles in, the trail crosses Minnehaha Creek. There have been good campsites on the ridge just before the crossing; check current camping rules.
4
Willow Pass junction 11,700' · 3.4 mi
Continue a little farther toward Buckskin Pass, then turn right (north) on the trail to Willow Pass.
5
Willow Pass 12,580' · 4.2 mi
Climb tundra, then red rock, to the pass.
6
Willow Basin 11,950' · 4.8 mi
Switchback down into Willow Basin, a huge tundra bowl dotted with red boulders and orange lichen. Just below 12,000 feet, before Willow Lake, take a trail heading west.
7
East Snowmass Pass 12,700' · 5.5 mi
Climb the side trail through white rubble to a pass between UN 13,350 and UN 13,015, marked by a post where the trail drops into East Snowmass Creek.
8
Summit 13,015' · 5.9 mi
From the pass, walk west up the ridge on small white rubble and talus, then south along the summit ridge to the rocky high point, overlooking Willow Basin.
Getting down
To skip most of the rubble, drop east-southeast from the summit on grass back to the trail below the pass, then return over Willow Pass.
If things go wrong
The trail is just below.
3D flyover
No 3D flyover for this peak
Above the pass the route climbs a short trailless ridge. A flyover only works when there is a set trail to trace. Without one, the line would be a guess, and a guess could send you the wrong way on the mountain. Use the step-by-step route with a good map and GPS track instead.
See the trail on video
No video yet
We haven’t found a good video of this route that matches the way we describe it. The route strip, junctions and 3D flyover show the way in the meantime.
This describes the route on a dry summer day. Most 13ers see few people, so there may be no one along behind you. Check recent conditions the week you go, carry a map, tell someone your plan, and turn around when the day tells you to.