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 · South Face from Twin Lakes
Overview
UN 13,559 is a remote 13er at the head of the East Brush Creek country, southeast of Castle Peak. From the Pearl Pass Road north of Crested Butte, a trail leads about 3.2 miles to Twin Lakes. From there you climb into a basin below the peak's steep south face, work through rock bands, and follow a hidden ramp to the southeast ridge just below the summit.
It is Class 3. There is one narrow gully of darker rock to scramble, and plenty of loose Elk Range scree and rubble. Route-finding on the face is tricky.
The round trip is about 7.9 miles with 3,150 feet of gain, including UN 13,173 to the west. From Twin Lakes it is about 1.5 miles and 1,750 feet. The trailhead needs a high-clearance vehicle.
Plan of the day
Start by
By 6 a.m. from the trailhead.
Turnaround
Be at the ramp about 300 feet below the summit by 10:30 a.m.
Crux
Finding a way through the rock bands on the south face and the short Class 3 gully that leads to the ramp.
Route-finding
Difficult. Zigzag through the rock bands, trending toward the west ridge, then look for an upward ramp heading east about 300 feet below the top. A late snow patch often marks it.
Water
Middle Brush Creek, Twin Lakes and small ponds above them. Filter it.
From Gunnison, take Highway 135 north through Almont toward Crested Butte. About 2 miles before Crested Butte, turn right onto County Road 738, the Pearl Pass Road. It starts paved through a subdivision, then turns to gravel.
Passenger cars can go 4 to 5 miles, to just past where the East River comes in. Park at a primitive camping area on the right, just as the road starts to climb. With high clearance, keep going: stay right at a junction about a mile later, ford West Brush Creek, and drive about 4.5 more miles to the Twin Lakes parking, which turns off the road to the left.
There are good primitive campsites with some trees at the trailhead, often busy on weekends.
Trail in the treesTundraTalus and screeScramblingExposed 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
Twin Lakes trailhead 10,425' · 0 mi
Cross Middle Brush Creek (wade it or find a way across), climb north a little, then turn northwest on Trail 402 toward Twin Lakes.
Watch for: The crossing can be high in early summer.
2
Into the wilderness 10,900' · 1.5 mi
The trail crosses open ground and patches of high forest on the east side of the creek, then enters the Maroon-Snowmass Wilderness. Overnight visitors must fill out a permit at the boundary.
3
Willows 11,300' · 2.7 mi
About half a mile below the lakes the trail crosses to the west side of the creek and pushes through thick, wet willows. It can be hard to follow here.
4
Twin Lakes 11,580' · 3.2 mi
Reach the north end of the upper lake. There are a few campsites near the lower lake, and more on tundra benches above.
5
Upper basin 12,350' · 3.5 mi
From the north end of the lake, head north, climbing roughly 800 feet, to a higher basin right below the south face.
6
Rock bands 12,900' · 3.75 mi
Climb a talus slope covered in grass through several cliff bands, zigzagging and trending toward the west ridge. You can also go all the way to the west ridge and follow it east to the top.
7
Dark gully and ramp 13,250' · 3.85 mi
About 300 feet below the summit, scramble a narrow gully of darker rock, then follow a ramp that slopes up to the east.
Watch for: Class 3. Loose rock.
8
Southeast ridge 13,350' · 3.9 mi
The ramp comes out at a small saddle on the southeast ridge about 200 feet below the top, with a great view of Castle Peak's jagged ridge.
9
Summit 13,559' · 3.95 mi
Walk and scramble up easier red rock to the summit.
Getting down
Reverse the ramp and the face. Strong parties continue west along the ridge to UN 13,173. That traverse is Class 3, takes 1 to 2 hours, and has one steep, exposed and loose downclimb.
If things go wrong
Below the rock bands, the basin leads straight back to the lake.
3D flyover
No 3D flyover for this peak
Above Twin Lakes the route climbs a steep, trailless face. 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.