St Louis Lake - 11.5 Miles Round-Trip

St Louis Lake (11,531') is located 5.75 miles from St Louis Creek Road in the Fraser Experimental Forest. This small but picturesque lake sits at treeline under a line of 12,000' peaks and ridges that form the Byers Peak Wilderness Boundary.

Trail Map | Photo Gallery

The hike begins at the now-permanent gate closure on St Louis Creek Road, where you must walk or bike 3.05 miles to reach the original trailhead (bikes are not allowed beyond this point).

From here the St Louis Lake Trail follows St Louis Creek through a healthy subalpine forest to the St Louis Pass Trail split, where it turns north and levels across a string of alpine meadows to the lake.

While the gate adds significant distance and climbing (6.1 miles and 780' total), it does thin crowds and improve chances of securing choice campsites at the lake:

Park at designated spots on either side of the road at the gate closure and backcountry board. The road rises steadily with little change to a washout at 2.85 miles, where you'll have to hop flowing water to reach the original trailhead (3.05 miles : 10.320').

Distances cited here are reset at this trailhead.

Cross the bridge and turn left beside St Louis Creek. The trail gradually steepens to a short log bridge (.78 miles : 10,855'), moderates to a crest, then drops to another log bridge (1.08 miles : 10,960').

It steepens back and arcs along the edge of a long, sloping meadow (1.35 miles : 11,170') to the St Louis Pass - St Louis Lake Trail split (1.55 miles  : 11,295'). 

The SLT turns north, drops and rises up to a cairn-marked switchback that leads right (1.7 miles). A left fork at this location is blocked off but can be confused for the main trail; if you see a pond on your left, you've gone the wrong way.

The trail emerges from thinning timber in a string of meadows that extend from treeline to the 12,000' ridge above (1.95 miles : 11,430'). It levels and rolls gently along the base of the meadows to St Louis Lake (2.7 miles : 11,531'). 

Cross the marshy, willow-lined outlet to reach established campsites perched on knolls over the lake, and arguably the best views from a high ridge over the east shore. 

The Fraser Experimental Forest was established in 1937 to study alpine and subalpine environments of the central Rockies, and specifically the relationship between forest management, water yield and water quality.

It's one of the only research sites in the Colorado Rockies that maintains long-term records on hydrology, forest structure and responses to forest management.

This 23,000-acre site enables researchers to conduct whole-ecosystem manipulations in watersheds that are representative of high elevation watersheds across the southern and central Rocky Mountains. FEF findings inform subalpine forest management decisions across Colorado.