Starting from the historic Chautauqua Park Ranger Station located on the southwest side of Boulder, the most direct route to this popular overlook and geologic feature is 1.6 miles with a nearly 1,300-foot vertical gain. Out of the parking lot the route starts on a gentle climb on a well-maintained trail across the slopey grasslands and into the shaded ponderosa pine forest. Once above the lower loops, the trail narrows some but is clear and well-marked with signs. Then the true vertical gain begins, with a mix of switchbacks and stone steps. Don’t be fooled by the crest over the eastern ridge coming down from Green Mountain. The trail dips about 150 vertical feet before starting the final climb to the arch.