Illinois Pass
USFS trail SNO-25
The route in 3D
Fly this trail over real terrain
USGS and partner elevation data build the terrain, and the US Forest Service centerline draws the route.
3.7 mi · Typical grade 8 to 10%
About 1,100 ft between the route's high and low points. An estimate from USGS elevation data, computed 2026-07-10; not measured in the field.
Trail facts
- Length
- 3.7 mi mapped
- Grade
- Typical grade 8 to 10% (USFS trail class TG03)
- Surface
- snow
- Designation
- National trail designation
- National forest
- Arapaho and Roosevelt National Forests
Length is the trail as the Forest Service maps it, not a trip distance. Hike out and back and you will cover it twice; check the shape of the route before you count on the figure.