National Forest Development Road 4220 is a hiking, biking, and horse trail in Clackamas County, Marion County, Wasco County, and Jefferson County, Oregon. It is within Mount Hood National Forest. It is 17.0 miles long and begins at 5,346 feet altitude. Traveling the entire trail is 34.0 miles with a total elevation gain of 2,855 feet. The Horsehoe Lake Campground camp site can be seen along the trail.