Arthurs Rock sits on the foothills of Lory State Park above Horsetooth Reservoir. The trail climbs up Well Gulch to a ridge that leads to the rocky summit of Arthurs Rock where you'll find picturesque views of the reservoir below and surrounding foothills. The trail then makes several switchbacks down the hillside through a thin forest of evergreens where it then parallels the foothills and the road through grasslands back to the trailhead.