Organ Pipe Cactus (ORPI): Vast "Secret" Wilderness on the Arizona-Mexico Border

National Park wilderness is something of a secret, even though it is a large part of many national parks and monuments.

We first noticed this a few years ago with Shenandoah Wilderness, the largest wilderness in Virginia, designated in 1976 and more than 40 percent of Shenandoah National Park. However National Park Service (NPS) emphasizes Skyline Drive, northern part of the Blue Ridge Parkway popular for motorcycle and auto cruising. Most park maps don’t show wilderness boundaries; and small brown portal signs mention “backcountry,” not wilderness, although there is a general section on wilderness on the park website.

We observed similar wilderness obfuscation in January 2018 hiking in Organ Pipe Cactus Wilderness in southern Arizona-one of NPS’ best kept secrets. Wilderness is 95 percent of this national monument sprawling over 517 square miles of Sonoran Desert along the Mexican border. Designated to protect organ pipe cactus, which resembles a pipe organ, the monument encompasses 90 percent of this unique cacti’s range in the United States.

The casual visitor to Organ Pipe would never know it is wilderness. Visitors find the usual National Park Service (NPS) facilities: visitor center, campground, a few hiking trails (old mining roads near the campground) and two scenic drives (“cherrystem” roads through wilderness). The area is a transit corridor for illegal immigrants and a few drug-runners, so the Border Patrol is a big player. The monument was closed for 11 years after a NPS law enforcement officer was shot pursuing drug cartel members who had fled across the border.
Since the monument reopened in 2014, emphasis has been to “welcome visitors back to their park,” according to the friendly visitor receptionist at the visitor center. Any plans for more trails? She hoped the anticipated new superintendent might emphasize this. In the meantime, the monument offers a few disparate “backcountry camping zones” hikers can use with a permit. The largest blocks west of the monument road are roadless, waterless and trailless, offering hiking on desert flats punctuated by washes and low mountains.

We created a “wilderness loop” that included plenty of “non-wilderness” hiking, using monument roads, but also variety and a probable water source-rather than packing three days’ worth (up to 6 gallons). It required creativity and a little risk because there is no dependable water in the monument and it had been an exceptionally dry fall/winter.

We planned to hike part of the Ajo Mountain Loop Road, possibly fill up at a water hole right off a trail, hike along the Ajo Mountains to a primitive campground at Alamo Canyon, and follow old county track back to complete our loop. On the way into the monument, we drove three miles up Alamo and stashed two-gallon jugs of water near the campground, hoping that wildlife would not disturb our stash that close to people but concerned that either Border Patrol or NPS agents might confiscate it. If that happened, we’d hitchhike back or beg water from friendly car campers at Alamo.

We left the visitor center with backcountry permits for two nights and plans/hopes to camp third night in self-pay Alamo. Luckily for us, the nine-mile hike on road was on a cool, overcast afternoon; welcome for carrying extra water. All afternoon we trudged towards dark Diablo and the soaring, golden Ajo mountains to Bull Pasture trailhead: shaded picnic area, parking and a toilet, all exempted from wilderness that surrounded us. Hiding our backpacks in wash under a mesquite tree out of sight of the road, we hiked up Estes Canyon, as the NPS mentioned a pool of water higher in the canyon. We also knew that beyond maintained trail, an unpublicized, unmarked but cairned route climbed to Ajo Peak. We wanted to do the climb to confirm our suspicion that ridge from Ajo to Alamo Canyon might be too rough for backpacks.
(We had originally considered hiking the ridge but could not find anyone who made it and further, the monument relief model at the visitor center showed steep drop-offs on the ridge but a relatively flat along the foot of the Ajo Mountains.)

The Estes trail, after crossing the canyon, immediately climbed the hill to meet a loop trail and continue climbing to Bull Pasture. A water hole visit would require a steep cross-country descent. Instead we hiked rocky switchbacks up to a pass above Bull Pasture, flat meadows and a spring named by early ranchers who wintered cattle there. As the slower hiker, I headed back down while nimble David descended into the washes seeking water.

He caught me on the last switchbacks as sunset lit up red cliffs above the trailhead. Yes, a few pools. We would come back the next morning, fill up, and check out the Ajo ridge route. We returned to our packs, hiked off the road a quarter mile and camped in a wilderness quadrant-not quite the required half mile off road but it was getting dark and sandy wash was preferable to desert pavement everywhere else.

Our camp was down Estes canyon below the road in soft sand in the wash. A faint aroma like a stable. Eventually we realized the source: the “wilderness toilet” at the trailhead!

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Route Map
Google Earth KML
Backcountry Regs
ORPI Closure
Visiting ORPI
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Cholla and saguaro cacti also abundant.
Cindy at portal sign for Organ Pipe Cactus Monument.
David on crest of Ajo Mountains 3000 feet above valley.
Multi-stemmed organ pipe cactus provides monument name.
Sunset from wilderness camp off the Old County Road.
Bighorn ewe and lamb near Ajo Peak.
Trailhead sign for Old County Road Trail.
Illegal Visits
ORPI Trip Details
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