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 over Castle Peak
Overview
Castleabra is the rugged 13er just west of Castle Peak, southwest of Aspen. This route walks up the Pearl Pass and Castle Creek roads into the basin north of Castle Peak, climbs over Castle's summit, and follows the connecting ridge west to Castleabra.
It is Class 3. The hard part is on the ridge: a gap more than 60 feet deep at the first saddle has to be bypassed on steep, loose ledges on the north side. The rest is loose rock and an easy final walk. Other routes, from Conundrum Hot Springs or from Cumberland Basin on the Crested Butte side, stay at Class 2+ but are longer.
The round trip is about 12.1 miles with 5,850 feet of gain from the Castle Creek ford. A good 4WD can drive to the upper basin and cut off about 8 miles of walking. You also get Castle Peak, a 14er, on the way.
Plan of the day
Start by
By 4:30 a.m. from the ford, or 6 a.m. from the upper basin.
Turnaround
Be on Castle Peak's summit by 9:30 a.m. You still have the ridge out and back to go.
Crux
Getting around the deep gap at the 13,580-foot saddle on loose ledges.
Route-finding
Moderate. Castle Peak has a trail. On the ridge, bypass the gap on the north side, then decide whether to contour below or climb over the 13,820-foot bump.
Water
Castle Creek and snowmelt in the upper basin. Filter it.
From the roundabout on Highway 82 just west of Aspen, take Castle Creek Road (County Road 15) about 11 miles to the old Ashcroft townsite. Continue 2 miles past the Toklat Lodge to a junction with a kiosk and room for several cars on the west side of the road. Low-clearance cars should park here.
Turn right onto the Pearl Pass Road (FR 102). It gets much rougher after about half a mile. After about 1.4 miles it fords Castle Creek, and there is a footbridge for hikers. We start the route at this ford. The ford can be deep during spring runoff.
Past the ford, a high-clearance 4WD can keep going, slowly, over very rocky road to the Pearl Pass junction and to the end of the road, in the high basin below Castle Peak's north side (about 12,775 feet). Fallen trees can block the way. There are no Forest Service campgrounds along the road, but there are a few primitive sites on FR 102 on both sides of the creek. Much of the land along Castle Creek Road is private.
RoadTundraRidgeTalus 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
Castle Creek ford 10,200' · 0 mi
Cross on the footbridge and walk southwest up the Pearl Pass Road.
2
Pearl Pass junction 11,000' · 1.8 mi
Where the road switchbacks for the third time, the Pearl Pass branch goes left. Take the right fork north into the Castle and Conundrum basin. There is parking here for a few 4WD vehicles.
3
Upper basin 12,775' · 4.05 mi
Walk the rough road about 2.25 more miles to its end just below 12,800 feet.
4
Castle Peak 14,265' · 5.05 mi
Climb about a mile to Castle's summit, either by the northeast ridge trail or up to the Castle-Conundrum saddle and south along the ridge. Both are Class 2. Expect snow for much of the summer.
Watch for: Loose dirt and gravel below the saddle once the snow melts.
5
Down the west ridge 13,900' · 5.3 mi
Head west down Castle's ridge on small loose rock. The first rock step is easy. The second may be easier on its north side, possibly along the top of a snowfield.
Watch for: Don't try to contour below Castle's summit. The slope is very unstable.
6
Deep gap 13,580' · 5.5 mi
At the first saddle a gap drops 60 feet or more. Climb down loose, sandy ledges on the north side into the gully below it, then climb back up about 100 feet.
Watch for: Class 3 on poor rock. Helmets strongly advised.
7
13,820-foot bump 13,820' · 5.75 mi
Contour the north side of this bump on steep, broken rock, or simply go over the top. Going over is often faster.
8
Summit 13,804' · 6.05 mi
The drop to the next saddle is easy. The last stretch to Castleabra is an easy walk on tundra, rock and maybe snow, with views into Conundrum and Cumberland basins.
Getting down
Go back along the ridge, bypassing the gap again, and back over or just below Castle's summit. From the Castle-Conundrum saddle you may be able to glissade into the basin, then walk the road back down.
If things go wrong
Until you leave Castle's summit, the regular Castle Peak routes are the way down.
3D flyover
No 3D flyover for this peak
Past Castle Peak the route follows a loose ridge with no trail. 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.