Organ Pipe Cactus National Monument is a huge, vast area of Sonoran desert along the Arizona - Mexico border. There is only one road through the reserve that runs from the town of Why to a small border crossing into Mexico. There is a small section of the park to the east of this road that presses up against the Ajo Mountains, and then an enormous expanse out to the west that eventually becomes wildlife reserve and continues to the California border. At the time of our visit, the majority of area in the park was closed to visitors due to "border concerns". What are border concerns? Well, there are two main ones. The first is the immigration issue and the fact that with all that untended border out there it would be pretty easy for park visitors to pick up "illegal immigrants" and whisk them away. The second is a security concern. While the immigrants are generally not dangerous, the drug runners and the immigrant traffickers often are. A park ranger was killed here in 2002 and the situation has deteriorated ever since.
There is no way to separate or ignore the political problems from the National Monument. The visitor center here looks more like army barracks than an NPS welcome center. Armed border patrol agents and armed park rangers congregate here in far larger numbers than you'd see in more visited parks. While we hiked in the Ajo Mountains, patrol helicopters flew back and forth overhead at relatively low altitudes. One thing that quickly becomes clear is that the border policy is completely ineffective and no one (the Park Service, visitors, or the Border Patrol) is really benefiting from the status quo. In early 2008, visiting the park was limited to the Ajo Mountain loop road, a short excursion out and back along what used to be the grand 60-mile loop through the park, and a couple of waysides and hiking trails off the main road through the park.
Having said all that, Organ Pipe is still an amazing place to visit and even though we would've liked to see more of the park, it's worth the trip out for even limited access. The Ajo loop is the only way to see any of the back country currently as hiking trails are also restricted and back-country camping is out of the question.
This is the namesake Organ Pipe cactus. They look similar to a Saguaro but they have many branches from the base. A lot of the park literature refers to them as 'rare'. Realistically, they're rare and unusual in the US - this is the only place you'll find them generally. There are plenty more across the border in Sonora and neighboring Mexican states.
There aren't many hiking trails accessible from the Ajo Mountain Loop Road. It's limited to a couple of trail heads at the far end of the loop which lead up into the Ajo mountains. However, most of the terrain near the road is easy enough to just wander out into (we wouldn't suggest going too far without a compass and a whole lot of water). Some of the best patches of wildflowers we found were while we were just wandering about vaguely in the vicinity of some of the pull-offs.
The far end of the loop runs right along the mountains and there are some interesting formations including the arch here, and the secluded plateau (if you ignore helicopters) in the Bull Pasture area.
Visiting in February seemed to have a couple major advantages. While the weather was very dry, it wasn't all that hot. More noticeably though, the recent rains led to a profusion of desert wildflowers including these here yellow things, and those pink things in the next picture (technical terms).
A few miles north of the visitor center in a featureless open plain, there is a dirt road winding east towards the mountains. When we visited there was absolutely no signage in either direction indicating that this turn off exists - it is however marked on the park map. This is Alamo Canyon Road and it dead-ends at a trail head. The trail leads a bit more than a mile into a canyon where it officially ends (there are unofficial connecting trails it appears) at an old abandoned ranch. Unless more of the park re-opens to visitors, this is definitely worth finding.
The trail follows a creek which was dry for most of its length on our hike. Eventually there are some old building remnants before the trail leads down to actual water and a creek crossing.
Just past this is the remains of a corral and cattle-gate. This is a particularly atmospheric part of the park and an excellent place for a picnic. We attempted to do a little extra exploring up the hillsides here but after a dozen or so acacia snags, decided it wasn't worth the effort.
This picture seems like a good place to point out that the desert sun is quite strong. We can also point out that if you're considering using this method to hide from the border patrol - you should probably not wear a watch.