To reach the 6.4-mile roundtrip Lower Rattlesnake Arches Trail, the shortest trail into the canyon apart from rafting down the Colorado River and climbing 1.5 miles up to the arches, you must drive one of the rough, high-clearance required Black Ridge Access Roads (Lower Black Ridge (11 miles) from 8/15 to 2/15, Upper (13 miles) from 4/15 to 8/15, both routes closed from 2/15 to 4/15)—approach is through Colorado National Monument and the Glade Park turnoff leading west to the McInnis Canyons National Conservation Area.
The beginning of the Black Ridge Access Road/McInnis Canyons National Conservation Area is located a quarter-mile from the Glade Park turnoff, then it’s an additional 10.5-miles on the 4WD road to the trailhead—although rough for most of its entirety, only the last 2 miles of the road require serious attention and high clearance—pick your lines carefully.
Once at the trailhead, follow the signs to the path leading into the canyon and eventually (0.5-miles from the trailhead) to the trail junction for Lower Rattlesnake Arches and First Arch Overlook—if time allows and you are so inclined, follow the First Arch Overlook Trail a half-mile to a viewpoint overlooking the top of Rainbow Arch, the last arch along the 4.4-mile out and back Lower Rattlesnake Arches Trail.