The granite boulders of the McDowell Mountains have been a playground of rock climbers for decades, long before the formation of the McDowell Sonoran Preserve. The geology in this part of Scottsdale on the north end of the McDowell Mountain range is characterized by large rock piles of rough-grained granite, similar to the famous rocks of Joshua Tree National Park.
During the creation of the McDowell Sonoran Preserve, which began in the early 1990s, citizens and members of the Arizona Mountaineering Club worked closely with Preserve planners to have rock climbing built into the master plan as a legitimate, sanctioned activity. Today, climbers can enjoy a variety of climbing routes in the Preserve, most of which are traditional style that require climbers to place all gear (bolts, pitons, etc.) required to protect against falls and to remove their gear after use.
Most of the popular climbing routes in the McDowell Sonoran Preserve are near the Toms Thumb Trailhead. The majority are trad climbing spots with a few options for sport climbing or bouldering. Here are three of my favorites.
Sven’s Slab: Access to Sven Slab from the Tom’s Thumb trailhead requires a short half-mile hike from the parking lot. This large granite boulder hosts a number of different routes including relatively beginner options like the ever-popular “Quaker Oats,” as well as one of the few sport climbing options in the area, challenging options that will hone your skills in disciplines like edge climbing, and multi-pitch climbs like Mouse Tracks.
Gardener’s Wall: Gardener’s Wall is just below Tom’s Thumb, so be prepared to start your day with a two-mile hike. The most classic route at Gardener’s Wall is Hanging Gardens. It’s a 5.6 two-pitch trad climb with the option to hike down off the back. Gardener’s wall also offers several sport climbing routes.
Toms Thumb Trailhead: This 200-foot-tall granite dome is the most prominent feature on the north end of the McDowell Mountains and has long been a favorite of climbers in the region. It was named for local climber Tom Kreuser who bagged the first ascent of the Thumb in 1948. Supposedly, there are more than 30 routes to the Thumb’s summit, including classics like Treiber’s Deception and Kreuser’s Route. Climbing the Thumb is a must for experienced climbers visiting Scottsdale. Approaching the routes on the Thumb requires a two-mile hike.
Things to know
The climbing season in the McDowell Sonoran Preserve is primarily winter and spring. In summer, the rock gets scorching hot. Whatever the season, you should be properly prepared for being outdoors in the desert. Some of these routes require quite a bit of hiking which makes water even more important. There is no water at the Tom’s Thumb trailhead, so bring plenty with you for the day.
The local REI in Paradise Valley has some great resources on climbing in the region if you’re looking for more insider tips, and offers occasional climbing classes. The Arizona Mountaineering Club puts together outings and community events as well.