St Louis Lake, Fraser Experimental Forest - St Louis Lake Trailhead, Summit County - Eagle County - Clear Creek County, Colorado

St Louis Lake - 11.5 miles

Fraser Experimental Forest - St Louis Lake Trailhead

St Louis Lake (11,531') in the Fraser Experimental Forest

St Louis Lake (11,531') in the Fraser Experimental Forest

Round-Trip Length: 11.5 miles (includes road walk)
Start-End Elevation: 9,540' - 11,531' (11,539' max elevation)
Elevation Change: +1,991' net elevation gain (+2,420' total roundtrip elevation gain)
Skill Level: Moderate
Dogs Allowed: Yes
Bikes Allowed: No
Horses Allowed: Yes
Related Trails:

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.

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Interactive GPS Topo Map

Key GPS Coordinates - DATUM WGS84

  • N39 51.095 W105 54.617 — 0.0 miles : Trailhead Gate on St Louis Creek Road
  • N39 50.396 W105 54.920 — 1.0 miles : Walk Road
  • N39 49.740 W105 55.580 — 2.0 miles : Walk Road
  • N39 49.057 W105 55.773 — 2.85 miles : Cross creek / washout
  • N39 48.893 W105 55.844 — 3.05 miles : Trailhead | Bike Rack
  • N39 48.533 W105 56.042 — .5 miles : Steady climb in subalpine forest
  • N39 48.439 W105 56.306 — .78 miles : Cross creek
  • N39 48.378 W105 56.594 — 1.08 miles : Dip to and cross log bridge
  • N39 48.408 W105 56.861 — 1.35 miles : Skirt meadow
  • N39 48.459 W105 57.022 — 1.55 miles : St Louis Lake Trail split
  • N39 48.573 W105 57.051 — 1.7 miles : Switchback @ cairn
  • N39 48.845 W105 57.001 — 2.05 miles : Rolling travel across meadows
  • N39 49.087 W105 57.004 — 2.35 miles : Cross short log bridge
  • N39 49.317 W105 56.874 — 2.7 miles : St Louis Lake (11,531')

Worth Noting

  • The Fraser Experimental Forest was established in 1937 to study alpine and subalpine environments of the central Rockies, specifically the relationship between forest management, water yield and water quality in the subalpine zone. Early research was oriented to timber, water and sediment production resulting from management practices. Current research has expanded to include nutrient cycling and carbon storage. Silviculture, soil and invasives are among other key areas of study.
  • Snow depth and water content, streamflow, sediment transport and climate monitoring stations are located throughout the FEF, some of which provide records dating back to 1941.

Camping and Backpacking Information

Backcountry Camping in the Fraser Experimental Forest and Byers Peak Wilderness

  • Dispersed camping in the Fraser Experimental Forest is restricted to between 100 feet and one mile of St. Louis Lake, and within the Byers Peak Wilderness. No fee or permit is required. 

  • Camping is prohibited within 100' of any trail, lake, stream or road, consistent with the above restrictions. Group size is limited to 12 heartbeats (people + dogs and stock combined).

  • Fires are not permitted in the Fraser Experimental Forest, except at Saint Louis Creek Campground if/when there are no fire restrictions are in place.. Fires are not permitted at St Louis Lake.
  • Use established sites whenever possible to minimize impact. Practice strict Leave No Trace camping.
  • Contact the Sulphur Ranger District (970.887.4100) or Rocky Mountain National Park (970.586.1242) for the latest weather, trail conditions and trail-specific guidelines when planning your trip.

Fishing Information

  • Fishing is permitted at St Louis Lake and within the Fraser Experimental Forest with a valid Colorado fishing license. 

Rules and Regulations

  • There is no fee to enter or hike in the Fraser Experimental Forest.  Backcountry camping is only permitted between 100 feet and one mile of St. Louis Lake.  

    There is no camping or dispersed camping in the Fraser Experimental Forest, except for Saint Louis Creek Campground (fee required) and between 100 feet and one mile of St. Louis Lake.  Camping is allowed in the Byers Peak Wilderness and the Vasquez Peak Wilderness (no fee required).

  • Camping is not permitted along roads in the Fraser Experimental Forest. Camping is only permitted in designated campgrounds (fee required) or in the wilderness (no fee required).

Directions to Trailhead

The St Louis Lake Trailhead is located on County Road 73 (aka St Louis Creek Road), 8.9 miles from Highway 40 in Fraser, CO.

Contact Information

Sulphur Ranger District
9 Ten Mile Drive
P.O. Box 10
Granby, Colorado 80446

Fraser Experimental Forest
4947 Grand County Rd. #73

Trip Reports

There are no trip reports on this trail.


"2nd time I hiked to the lake to fish: 1st time fly fished, no activity. 2nd time spin fished, also No fish activity, no bites, no fish spotted in water. I believe this lake is barren for some untold reason. Water is crystal clear and deep. Scenery is beautiful and for just a scenic bike and hike it is great."
frank palski  -  Winter Park  -  Date Posted: September 15, 2018


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