THE PERFECT WEEKEND IN ORGAN PIPE CACTUS NATIONAL MONUMENT

When European immigrants ventured into the southwest cornerof Arizona Territory in the late19th century, they considered the SonoranDesert a barren wasteland and saw littleof value except the gold, silver and cop-per they were seeking. But eventually, theland became treasured for somethingelse: cactuses. In 1937, President FranklinRoosevelt established Organ Pipe CactusNational Monument to protect one of therichest Sonoran Desert habitats in the UnitedStates. And in 1976, the park was named anInternational Biosphere Reserve for its abun-dance of unique plant life. Within the monu-ment's 330,000 acres are 31 different cactusspecies, including the only large stands oforgan pipe cactuses in the nation. Therealso are vast expanses of saguaros and rarersenita cactuses.

Day 1

Start your Sonoran Desert weekend on the21-mile Ajo Mountain Drive, a graded loop roadeast of State Route 85 that leads into the tow-ering Ajo Range. Pick up a free interpretiveguide for the route at the park's visitors cen-ter. The drive itself takes about two hours,but you'll want to allow plenty of extra timefor hiking, picnicking and cactus gazingalong the way. "This drive is one of my favor-ite things to do in the park - you get a littlebit of everything," says Karen Ceballos,a ranger at the monument. "It showcases somany different plants and takes you way upinto the mountains with amazing views intoMexico and of organ pipe stands."

From park headquarters, make your waynortheast on the one-way loop throughcactus-studded basins, with Tillotson Peak onyour left. Dead ahead are the jagged volcaniccliffs of the Ajo Range and 4,800-foot MountAjo. The road twists its way up to the base ofthe sheer rhyolite cliffs and the Arch CanyonTrailhead. Located around the halfway point ofthe drive, this is a great place to stretch yourlegs. Scramble up the 1-mile path that leadsto the entrance of the narrow canyon, wherethere are two natural arches: a 90-foot-widespan, and a smaller arch on top of it. The pic-nic area at the trailhead is a scenic lunch spot.

Continuing on the drive, the road loopsback to the south and soon reaches the EstesCanyon-Bull Pasture Trailhead. Ceballos recom-mends the Bull Pasture loop route as thebest hike in the park. The roughly 4-mile(round-trip) route climbs 900 feet up to thegrassy Bull Pasture Saddle, where ranchers oncegrazed their cattle. The loop then circles backthrough the riparian oasis of Estes Canyon."I love this hike," Ceballos says. "It is a bit of astrenuous climb, but you are rewarded withincredible views of Mexico's Cubabi Moun-tains and Mount Ajo. And on the way downthrough Estes Canyon, there are a lot of wild-life and birding opportunities."

mends the Bull Pasture loop route as thebest hike in the park. The roughly 4-mile(round-trip) route climbs 900 feet up to thegrassy Bull Pasture Saddle, where ranchers oncegrazed their cattle. The loop then circles backthrough the riparian oasis of Estes Canyon."I love this hike," Ceballos says. "It is a bit of astrenuous climb, but you are rewarded withincredible views of Mexico's Cubabi Moun-tains and Mount Ajo. And on the way downthrough Estes Canyon, there are a lot of wild-life and birding opportunities."

Once you're back at the car, continue driving southwest, into desert basins flanked bythe Diablo Mountains, until you return to parkheadquarters. If you can snag one of the fourcampsites at Alamo Campground, pitch your tent for the night at this primitive site, which is north of park headquarters and 3 miles east of SR 85. At sunset, the cliffs of the Ajo Range glow pink and orange. The sites are first come, first served, so you may want to claim your campsite before tackling Ajo Mountain Drive. Otherwise, there are plenty of sites that can be reserved in advance at the park's developed Twin Peaks Campground, next to the visitors center.

Eat + Sleep

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United States, exist only in Organ Pipe. Back on Puerto Blanco Drive, the road becomes gravel and one-way as you wind around Pinkley Peak. Drift west, then south through an endless green desert until you reach a “T” intersection at the U.S.-Mexico border. Hang a right on the short spur road to visit Quitobaquito Springs. This rare riparian area includes a man-made pond that attracts abundant bird life. It also is home to three species that occur naturally nowhere else in the U.S.: the Quitobaquito spring snail, the Sonoyta mud turtle and the desert caper. Enjoy a picnic here and contemplate that archaeological evidence shows humans have been visiting the springs for more than 16,000 years. Continue along the border to the junction with SR 85, then make your way back to the visitors center. After setting up camp at Twin Peaks Campground, enjoy one of the best sunset perches in the park on the Desert View Trail. The 1.2-mile loop trail leading from the campground climbs a ridge with benches; from there, you can watch the desert bajadas below radiate with the day's last light as stands of organ pipes turn a neon green.

Day 2

Spend the day on a leisurely drive along 37-mile Puerto Blanco Drive as it winds its way around the Puerto Blanco Mountains and parallels the U.S.-Mexico border.

This road is less traveled than Ajo Mountain Drive and provides a chance to experience the expansive space and quiet of the desert in utter solitude. Some sections of the route are rutted gravel, and a high-clearance vehicle, such as an SUV or truck, is recommended.

From the visitors center, head north on Puerto Blanco Drive; in about 4 miles, you'll arrive at the Red Tanks-Senita Basin Trailhead. A 3-mile ramble through this flat desert wash will take you through the natural water catchment Red Tanks Tinaja, a desert wildlife oasis. The path then leads into Senita Basin, where a 1-mile loop route offers the chance to see wild senita cactuses which, in the

Day 3

Top off your Organ Pipe adventure with one last hike. The 2.2-mile (one way) Victoria Mine Trail begins at the campground and leads to the best-preserved mining ruins in the monument. The Victoria Mine produced gold and silver from the 1880s to the 1910s, although mining continued sporadically until the monument received wilderness designation in 1976. The stone remains of a general store are still standing, and abandoned mine shafts and tailings piles surround the store as a reminder of a previous era.