I first glimpsed Lonesome Mountain on a hike of Beartooth Butte and was instantly smitten by the distinctively shaped summit.
A year later, I returned with two adventurous friends to climb it. We braved bogs, creek crossings and some truly world-class mosquitoes to make our way up to the rocky 3rd class summit cap. Some easy 3rd classing led to the summit and rewarded us with sweeping spectacular views. What a great day!
Interested In Doing This Hike?
We started at Beartooth Lake campgound and followed the trail northwest (along Beartooth Creek) for 2.5 miles before leaving it to go cross-country for another 3 miles to the summit. Lonesome Mountain is visible well before this point, so you just head toward it, picking the path of least resistance. There are lakes scattered throughout this area and you might have to walk around some of them. Lonesome Lake lies at the base of its namesake peak and we skirted it on the right. The last few hundred feet to the summit are easy 3rd class scrambling on big granite boulders. This approach takes you to the south face, which is the easiest.
We made a loop out of this hike and returned to the trailhead by bushwhacking down past Becker Lake and picking up the Beauty Lake trail. It was just under 6 miles to get out this way. We later learned there was a trail around the east side of Becker Lake (it’s not on NAD27 maps). Using it would have made things a lot easier!
The net elevation gain from trailhead to summit was just under 2500 feet. However, there were lots of ups and downs on this hike and I think our total elevation gain was much higher.
Other options are to start from Island Lake (longer but I hear it’s less boggy) or from the Clay Butte Lookout.