32 mi southwest of Ajo; from Ajo, backtrack to Why and take AZ 85 south for 22 mi to reach the visitor center.
Organ Pipe Cactus National Monument, abutting Cabeza Prieta National Wildlife Refuge but much more accessible to visitors, is the largest habitat north of the border for organ-pipe cacti. These multi-armed cousins of the saguaro are fairly common in Mexico but rare in the United States. Because they tend to grow on south-facing slopes, you won't be able to see many of them unless you take one of the two scenic loop drives: the 21-mi Ajo Mountain Drive or the 53-mi Puerto Blanco Drive, both on winding, graded one-way dirt roads.
Be aware that Organ Pipe has become an illegal border crossing hot spot. Migrant workers and drug traffickers cross from Mexico under cover of darkness. At this writing Puerto Blanco Drive was closed to the public. A two-way road that only travels 5 of the 53 mi on Puerto Blanco Drive is open, but the rest of the road will remain closed due to continuing concerns over its proximity to the U.S.-Mexico border. Even so, park officials emphasize that tourists have only occasionally been the victims of isolated property crimes—primarily theft of personal items from parked cars. Visitors are advised by rangers to keep valuables locked and out of plain view and not to initiate contact with groups of strangers whom they may encounter on hiking trails.
A campground at the monument has 208 RV (no hookups) and tent sites. Facilities include a dump station, flush toilets, grills, and picnic tables.
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