Climb almost 4,000 feet from the floor of the Gallatin Valley to the summit of Baldy Mountain. The route is long, steep, and exposed, so be prepared for a big day out—remember that you have to descend everything you climb, and that there are multiple false summits. Because the entire run is along a ridge, the views are spectacular as the trail passes through patches of forest and wide open meadows full of summer wildflowers. But running along a ridge also means that there's not much shade so it can be hot, or it can be quite windy and cold.
Start from the same parking as the College M Trail #511
. If you want to begin the brutal climbing immediately, head left up the Bridger Ridge Trail #513
from the trailhead. For a mellower start, follow the College M Trail #511
until it reaches the ridge above the M and rejoins the Bridger Ridge Trail #513
. From there, follow the Bridger Ridge Trail #513
until you reach the summit of Baldy Mountain.
The ridge is long and can be exposed to either harsh sun or relentless winds, so bring adequate water, sunscreen, and/or layers, depending on the weather. It would be quite difficult to get lost along this route because the M trails are all well-established, and the trail along ridge itself is prominent and easy to follow. As you ascend the ridge and pass treeline, be prepared for multiple disheartening false summits! The view from the top is excellent though, with town far below and the Gallatin Range in the distance.
Much of the trail is loose dirt or rocks, so be careful with your footing—especially on the descent. Because this is a popular route due to its proximity to town and its fantastic views, expect to encounter other runners, especially around the M trails.
Lots of wildflowers in the summer, and the occasional mountain goat as well.