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dblack Trinity and Silex Lake Route

  5.0 ( 3 ) Favorite


34.4 mile 55.4 kilometer loop
78% Runnable
Extremely Difficult


Ascent: 9,059' 2,761 m
Descent: -9,059' -2,761 m
High: 12,859' 3,919 m
Low: 10,525' 3,208 m


Avg Grade: 10% (6°)
Max Grade: 78% (38°)


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Trail shared by Thomas David Kehoe

A multi-day trip into Colorado's most rugged and remote wilderness.

Thomas David Kehoe

Features Lake · River/Creek · Views · Wildflowers · Wildlife


This run travels to a wilderness in one of the most rugged and remote areas of Colorado. It's a large space where you won't see anyone for days. There are many nearby peaks to climb, some of which have only been climbed by a few people. Because the country this run covers is so rugged, I recommend setting up a base camp at Trinity Lake and then doing day excursions or exploratory climbs to nearby summits to make a longer trip to suit your adventurer's appetite.

Need to Know

  • This run involves sections of cross-country travel through the wilderness. Be prepared and observe "leave no trace" principles.
  • As mapped, this run starts at the Highland Mary Lakes Trailhead which is okay for cars, except the crossing at Cunningham Creek just before the trailhead. To reach the trailhead take Route 110 out of Silverton for four miles, then cross the Animas River at Beartown. Turn right onto CR 4 and go two miles to the Stony Pass junction. Stay right in CR 4 another 2.5 miles to the trailhead. There's parking for a dozen cars.
  • Alternative access points include the Molas Pass Trailhead (which features a paved road, but a difficult run out of the Vestal Basin), Hunchback Pass near Kite Lake (requires a 28-mile drive on jeep trails that are fine for a Toyota 4Runner, but not a Subaru Outback), or head up Vallecito Creek from Vallecito Reservoir (requires an additional 16 mile run to Stormy Gulch).


From the trailhead, travel south for 0.3 miles and turn left onto the Cunningham Gulch Trail Connector to start a steady grinding climb. At the Cunningham Gulch trail junction, keep right toward a shared section of the Colorado/Continental Divide Trail at 1.8 miles. Turn right and continue to the south.

The next few miles go by more easily and a beautiful campsite is passed at 2.4 miles with a few more 0.3 miles down the trail. At 3.1 miles there's a junction for the Whitehead Trail which travels west past Verde and Lost Lake. At mile five, the CDT and Colorado Trail splits. Keep left at this and the next intersection to stay with the CDT.

The trail then drops down to the Bear Creek Jeep trail and reaches the Hunchback Pass trailhead at 7.2 miles and follows things up with a steady but not overly steep climb up and over Hunchback Pass at 8.5 miles (12,480'). The trail then descends towards Vallecito Creek. At 9.9 miles the Continental Divide Trail turns left at a junction with the Vallecito Trail #529. Turn right to descend along Nebo Creek. There are two good campsites spread out below the trail junction.

Stormy Gulch is reached at 11.5 miles and there is a large meadow where you could camp, but depending on when you visit, there may be zillions of flies.

The next portion of this run departs from maintained trails. Head west through the meadow and across Vallecito Creek (easy to cross in late July). The first 0.9 miles follows an old, overgrown trail. The first half-mile is relatively easy but the second half-mile has many downed trees and it's easy to lose the trail. Cross Trinity Creek here (there are two campsites on the other side of the water), you'll find that the route is now easy to follow. There's another creek crossing very soon.

Around 13.4 miles runners will reach a junction with the Lake Silex Route to the left and Trinity Lake Route continuing ahead. There are a couple of campsites near the junction. Continuing to the right soon leads to a large pond marked with a rock cairn. Trinity Lake is getting close, just a bit more than a half-mile away. There are several campsites once you reach the shores of the lake (but consider making camp at a pond 0.4 miles up the trail if you like dawn/sunset photography or just enjoy a view).

This is a great place to set up a base camp and complete the next part of the loop as a day-trip. The Trinity Pass Route is difficult as it is, and you won't really want a heavy pack to complicate things. Plan on taking your time to safely navigate and be prepared with plenty of water and snacks and appropriate outerwear.

Trinity Pass sits about 0.8 miles away (12,928'). The east side of the pass is loose shale, and while there is no exposure, each step knocks rocks down. The west side of the pass has a route marked with cairns that follows various ledges between cliffs. After passing Vestal Lake and Wham Ridge, the route turns to the south.

The next pass between Vestal Lake and Balsam Lake is unnamed. The north side of the pass is made of steep loose rocks, similar to the east side of Trinity Pass. The south side of the pass has a route marked by cairns across boulder fields to Balsam Creek. Expect this mile to take an hour or more.

At Balsam Creek, there is a nice camp spot between two ponds. A little under a mile above the creek is another unnamed pass that separates Balsam Creek and Lake Silex. Sitting on the other side of this easy pass is a steep-sided boulder covered valley. Lake Silex is a deep blue at the bottom of the valley, so far down you rarely glimpse it.

There's nowhere to camp in this valley. However, the short Lake Silex Route leads from the pass to the intersection with the Trinity Lake Route. If you opted for the day-route to complete the lollipop portion of the loop, turn to the left and head back to the base camp at Trinity Lake. If you didn't heed the earlier recommendation, you can turn right to begin the long journey back to the trailhead.

The return will still take some effort, but overall it's easier than the way in and the views are just as spectacular!

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