Cathedral Peak is one of the Colorado Centennial 13ers meaning it's one of the highest 100 ranked peaks in Colorado. It lies 1.7 miles north of its more famous neighbor, Castle Peak (14,275 feet). Although, Castle Peak has a class 2 hike all the way to its summit, Cathedral Peak does not. This peak is well named, for it has high and wild rock pinnacles on its north and south ridges and on the beautiful east ridge which one can see from Cathedral Lake. Most people climb Cathedral Peak in June or July when snow still resides in one of the east facing gullies which are climbed to reach the standard south ridge. In late summer and fall, the climb up the gully is a dangerous, loose and tedious task on some of the worst rock in Colorado. Despite this, the summit can be reached with Class 3 scrambling. Cathedral Peak is about 57 feet short of being a much more popular hike. If you want some solitude and don’t mind the loose stuff, this makes for a very gratifying day. Views of all the major Elk Range peaks are spectacular from the summit.
RT from trailhead to summit - 9 miles and 4,200 feet elevation gain
RT from trailhead to Cathedral Lake - 6 miles and 2,000 feet elevation gain
The climb starts at the Cathedral Lake trailhead which is 9,980 feet elevation. From the north side of Aspen, Colorado, there is a large round-about just outside of town marking the intersection of Highway 82, Maroon Creek Road and Castle Creek Road. Leave Highway 82 and take the Castle Creek paved road exactly 12 miles south. After passing the ghost town of Ashcroft at mile 11, look for a “Trailhead” sign on the right and turn right on an improved dirt road. It’s only a half-mile to the actual trailhead which sits among a beautiful aspen grove and offers plenty of parking. This is the Cathedral Lake and Electric Pass Trailhead. You can car camp here for free.
South Ridge Standard - Class 3 + Steep Snow
This is the standard route on this mountain. From the trailhead described above, follow the very nice trail through large aspen groves and up to Cathedral Lake about 3 miles from the trailhead. The lake sits at 12,000 feet right around treeline. The first dramatic peak you see as you ascend this trail is not Cathedral Peak, but the 13,540 foot Malamute Peak. There is a signed junction shortly before reaching the lake. Do not head right towards Electric Pass but instead stay left to Cathedral Lake. Once at the lake, you still cannot see the actual summit from here, however you can view Cathedral’s south ridge and the impressive east ridge that looms directly above to the right. Also, this where you can preview the east gully you must ascend. To determine the gully, follow the south ridge down to its lowest point and the gully that descends from that point is your route. There is another gully further left on the south side of a small tower near the low point of the south ridge. This gully is NOT the correct one. Traverse around the north side of the lake and locate a small mine at the base of Cathedral’s dramatic east ridge. Once at the mine, locate a faint climbers trail to the left and follow it up into the upper basin where you can finally see Cathedral Peak’s summit and the upper east face.
East Face - Class 3 + Very Steep Snow
"Cathedral Peak's East Face is one of the Elks best snow climbs and ski descents. The route climbs from Cathedral Lake up the East Face up a narrow couloir. The East Face joins the South Ridge just below the summit. The whole route is skiable from the summit if attempted early enough. The ski descent is rated as a D14 on the D Scale. Alternatively, the South Ridge can be used a descent." - Brian Kalet
If you are comfortable with an ice axe and crampons a late spring ascent of Cathedral Peak is the best choice. I have spoken to a few who wouldn’t consider Cathedral Peak any other way, but this peak is definitely worth climbing in late summer after all the snow has melted. The Castle Creek paved road is plowed all the way to Ashcroft in the winter.
Be sure you have an ice axe, crampons, warm clothes and wear a helmet on this peak!
Camping in the Cathedral Lake area is permitted as long as you camp 200 ft. from the lake. There are no campground in Casle Creek Valley. I suspect you could go down to the end of Castle Creek road and take a few of the dirt roads and find some pull-offs available. Obviously you can stay in the Roaring Fork Valley, plenty of lodging in Basalt, Aspen, or Snowmass.
Here is an excellent link for Colorado Camping Reservations. An additional reservation fee of $8.65 is charged for this service. It might be worth it considering it can be difficult getting a campsite in this area.