SCENIC DRIVE

scenic DRIVE AJO MOUNTAIN DRIVE Organ Pipe Cactus National Monument is best known for its namesake, but at least 30 other cactus species can be found in the park, along with steep mountains, dramatic views and a 20-mile scenic drive. BY NOAH AUSTIN/PHOTOGRAPHS BY REBECCA WILKS

Organ Pipe Cactus National Monument covers 516 square miles of Southern Arizona, so you could spend a month there and not see all of this isolated, biodiverse jewel of the national park system. But most people spend significantly less than a month thereand Ajo Mountain Drive is for them. Careful drivers can navigate this 20-mile loop in most vehicles, and it traverses much of what makes Organ Pipe great, including unique desert flora, steep mountains and dramatic views.

Before you embark, stop at the monument's visitors center to pay your entrance fee and pick up a guide to the route; numbered stakes along the road correspond to entries in the guide. Then, head east on Ajo Mountain Drive, which is across State Route 85 from the visitors center. In the early going, you'll see plenty of Sonoran Desert staples such as saguaros, chollas and ocotillos along this wide, washboarded dirt road. Straight ahead, to the east, are the craggy peaks of the Ajo Range, which is topped by 4,819-foot Mount Ajo. You'll get a closer look at the mountains later, but for now, enjoy the view along the road - which splits and becomes a narrower, one-way route at Mile 2.

Two miles past the split, you'll spot your first organ pipe cactus (Stenocereus