Hike Hayden Peak and Mount Agassiz Uinta-Wasatch-Cache National Forest, UT

Aug 17, 2022 — Hayden Peak and Mount Agassiz tower over the scenic Mirror Lake Highway that runs through the western Uintas. Neither peak has a trail to its summit, so I was interested in tackling the ridgeline separating the two in order to form a loop rather than do each individually. I started from the popular Highline Trailhead, but rather than following this trail (I'd be coming back that way later from Mount Agassiz), I headed east along a good social trail toward the base of Hayden Peak.

My initial plan was to ascend via a spur ridge that juts out toward the parking lot, but I think I missed a turn-off because I'm a ditz and ended up ascending to the north of this spur ridge instead. Rather than backtrack, I followed this trail as it led to a steep-looking slope that narrowed into a gully. From below the gully looked like it would be perfectly fine as an option for gaining the main ridgeline above, if not the most pleasant. I started up the Class 2 talus slope that steepened into some light Class 2+/3 hardpan stuff as entered the gully. With some occasional careful foot placement and some bear-crawling, I was at the crest. I later asked my friend Sam Grant (who had done this route as well as the spur ridge option I missed), and he made it seem like neither were exceptional routes, though the spur ridge has a nice Class 4 cliff band move and some other fun scrambling. I guess choose which you prefer, though in hindsight I would have preferred to try the spur ridge.

I started north toward Hayden Peak, excellent views into Middle Basin to the east and toward Mount Agassiz behind me as Class 2 obstacles led more-or-less along the ridge crest. Keeping left around the first obvious headwall, more Class 2/2+ scrambling wrapped around the feature's base and then up on fun and blocky boulders. A flatter section led to the second headwall, which was guarded by a jumble of blocky stuff. Hayden Peak's summit was just above. There seem to be two cairned routes to get there. The one keeping left seemed like it would be a bit more tedious, so I kept to the right on a wide Class 2 ledge that wrapped around to the east side of the peak. The ledge faded away and I started up to the left where Class 2 scrambling on massive boulders ascended directly toward the summit. A single Class 3 move to pull a small lip just below the summit was the only crux I found.

I backtracked from Hayden Peak and started toward Mount Agassiz. The terrain along the ridgeline here was fractured and very cool, large crevasses forming a bit of a maze. After a bit of hiking on rocky terrain, I reached the point where the ridgeline traverse would become more work. A slope led down about 100 feet to a small cliff, which I avoided on its right and pulled a short Class 3 move to get above it and back to the ridgeline. Shortly after I saw the next obstacle, a towering headwall that looked pretty scary from here. A Class 2 descent to a small notch at the base of the headwall somehow made it clear that this section wouldn't actually be more than a hundred feet or so of Class 2+. Once above the second obstacle I made my way along the ridge crest until Mount Agassiz came into view again. Separating me from the peak was a saddle about 500 feet below. The boulders are a bit loose here and I recommend keeping to the right of the crest where it's a bit less steep.

Once at the saddle, I started up to Mount Agassiz. I kept just to the right of the ridge crest until just past 12000', where the crest looked less jagged. Here I gained the crest and then fun, solid Class 2/3 terraces, gaps, and even a narrow slot-like feature led to the summit. Staying right of the crest looked fine too, but definitely more loose and without the fun sections. Just a note in hindsight: I'm not sure if it would actually work out, but it could be possible descend from Mount Agassiz's east ridge to Blue Lake and pick up the Skyline Trail from there, though this would have added over 3 miles to the hike and I didn't know how if the ridge would go, plus I was very much out of food.

I dropped back to the saddle from Mount Agassiz and headed south down the steep Class 2 slope. The goal was to bushwhack down to the Highline Trail about a mile or so away. A gorgeous meadow met me past the slope, which led into the forest. Unfortunately this area was burned somewhat recently, but that meant at least I'd continue to get some views. The burn area faded away and I was back in the forest, where I did have some minor bushwhacking, though it was pretty easy to just dodge downed trees and the small sections of brush. There were a couple of small marshes/meadows that served as brief escapes from the trees. I made it to the Highline Trail and took it north, regaining some vertical elevation as I made my way back to the trailhead.