Marion Lake via Granite Canyon

Marion Lake via Granite Canyon is an 18.8-mile out-and-back from Granite Canyon Trailhead, with 3,510 feet of total climbing. The published time is 9–13 hours; plan around 12, including a real stop at the lake. It’s a very strenuous, high-country hike, best saved for a day when you’re ready for a long climb and a long walk back. A separate Marion Lake route starts at Rendezvous Mountain and loops through both forks of Granite Canyon; that’s a different itinerary, not a shortcut to add to this one.

The first stretch crosses a sagebrush meadow with views of Mount Hunt, Prospectors Mountain, and Albright Peak, then enters aspen and forest. At about two-thirds of a mile, the path crosses Granite Creek. Around 1.5 miles in, take the right at the Valley Trail junction, cross the creek again, then bear left at the fork to stay on Granite Canyon Trail. There are several junctions on this long approach, so keep checking that you’re following the north fork toward Marion Lake.

The trail alternates between woods and open ground, climbing in and out of the trees. It’s often narrow and steep, with steps and switchbacks. Higher up, the canyon opens into flower meadows and views back down the drainage to the surrounding peaks. Early summer brings bright wildflowers through these open stretches; the lake is the payoff, but the changing canyon scenery is what keeps the climb from feeling like one long forest tunnel.

The Upper Granite Canyon Patrol Cabin is a useful landmark along the route. The Civilian Conservation Corps built it in 1935; it was rehabilitated in 2013 after deteriorating. The name Granite Canyon is a little misleading: early explorers thought the upper canyon’s rock was igneous granite, but it is metamorphic metagabbro. That’s a good detail to keep in mind when the trail leaves the trees and the rock walls become part of the view.

The final climb steepens before the route reaches a small alpine lake in a cirque below Housetop Mountain. The lake sits beneath a high cliff wall, with conifers and meadow around its shore. Give yourself time to rest before retracing the same trail. For a photo, include the water and the cliff together; a tight shot of the rock misses the shape of the basin. The mapped line ends about 100 metres east of the shoreline, even though the hike itself continues to the lake, so don’t treat the digital endpoint as the turnaround.