Castle Dome Mountains

Some drives require little more than a full tank of gas and an hour or so. This isn’t one of those. The prerequisites here include a high-clearance vehicle, four-wheel-drive, and plenty of time and patience — it takes three hours or longer, and for most of the 31-mile route, if your speedometer ticks past 10, you’re risking a flat tire or a dented oil pan. If you’re up for the challenge, buckle up and head to the Castle Dome Mountains, northeast of Yuma, for a true back-road adventure that’s spectacularly scenic.

From U.S. Route 95 south of Quartzsite, head east on King Road into Kofa National Wildlife Refuge, a sprawling preserve that covers its namesake mountain range in its northern section, as well as the smaller Castle Domes to the south. You’ll wind between two small peaks as you pass the Hidden Valley Hills, topped by 2,671-foot High Peak, on the left. Soon, you’ll be in a large field of chollas and ocotillos, which anchor a view of the Kofas to the northeast.

At Mile 6.1, a sign points you down McPherson Pass Road, and you’ll immediately see why four-wheel-drive is required for this drive. Ruts, washes and exposed bedrock are everywhere, and slow, careful driving is essential. It’s worth it for the view of Castle Dome Peak (3,780 feet) straight ahead, and along the road, you might see blooms of Mexican goldpoppies, lupines and other Sonoran Desert wildflowers in March and April.

The narrow road winds through stands of massive ocotillos, along with saguaros, on a particularly rough stretch that ends at Mile 10. Just past it is a clearing with expansive views of Castle Dome Peak to the south and the sprawling King Valley to the northeast. Then, it’s back to bumping along until Mile 12, when the road curves to the southwest and heads toward McPherson Pass. The vegetation along the road gets thicker as steep-walled peaks close in on both sides. And after you crest a hill at Mile 14.3, you’ll find another clearing, this one in an idyllic valley filled with cactuses and surrounded by craggy mountains. Here, look for desert bighorn sheep, the reason the wildlife refuge was created in 1939.

This is a good place to stretch your legs (and arms), because the next few miles are as gnarly as they are beautiful. If you’re with a group, take turns driving so everyone can enjoy the views of peaks towering over the road and distant ranges to the west and southwest. Finally, at Mile 18 or so, the road smooths a bit as it descends out of the mountains.

At Mile 19.5, you’ll come to a “Y” intersection. This road once continued south to the Castle Dome Museum, which features numerous buildings and artifacts from the area’s mining history — some in their original locations, others relocated when these mountains became part of the wildlife refuge. Today, though, you’ll bear right and follow a winding bypass road that offers good views of the other side of Castle Dome Peak.

The bypass road ends at a “T” intersection with Castle Dome Mine Road. You can visit the museum by turning left; otherwise, turn right and follow this wide, smooth road out of the refuge and through the U.S. Army’s Yuma Proving Ground. You’ll return to pavement a couple of miles before the drive ends at U.S. 95, where a 65 mph speed limit is your reward for the patience it took to explore the Castle Dome Mountains.