County Road 100 is a hiking, biking, and horse trail in Weld County, Colorado. It is within Pawnee National Grassland. It is 2.9 miles long and begins at 4,709 feet altitude. Traveling the entire trail is 5.8 miles with a total elevation gain of 364 feet. The Bringleson Reservoir (elevation 4,770 feet) reservoir can be seen along the trail. There is also a water along the trail.