Marked by a white road marker with the number "10" on it, this road pulloff faces the Ajo Mountains: crumbly and bulbous red-colored mountains made of rhyolite and tuff rock. At the top of one of the mountain faces is a natural double arch, with a larger, wider arch on the bottom and a much smaller arch sitting on the top. This stop faces Arch Canyon, a lush canyon filled with palo verde, mesquite and other desert shrubs and trees.

<h3><b>Stop 10 </b></h3> <h2><b>The Cooler Climate of Canyon Country</b></h2> <br /> The Ajo Mountains receive more rain than any other part of the monument and have cooler summer weather. Reflecting the high country climate, the jojoba bush and the evergreen scrub community is restricted to the rocky outcrops, boulder slopes and deep canyons of the Ajo range.<br /> <br /> The high country plant communities support the elusive bighorn sheep and white tail deer that inhabit this area. Their hooves have adapted to allow them to cling to rocky slopes and steep ravines. The mountain environment is especially attractive to turkey vultures, eagles and ravens that nest in the canyons and ride the air currents that canyons provide. Caves and rock shelters within the canyon walls are also great roosting places for bats. The lesser long-nosed bats, which have already been mentioned, especially like to roost in the cool shaded canyons during the heat of a summer day.<br /> <br /> Just up the road is the Arch Canyon trailhead parking. There are picnic tables and signs describing the geology of arch formation here in the monument, as well as a two-mile round trip trail that leads hikers into the foothills of the high country. The parking area is also a great place to pull over for scenic views of the arches – there are two visible, if you look closely.

The moon rises behind two natural rock arches, stacked upon one another.

Arches and Moon

Location

Ajo Mountain Drive Stop 10

Look closely. Look again. The sights and sounds of Organ Pipe Cactus National Monument, an International Biosphere Reserve, reveal a thriving community of plants and animals. Human stories echo throughout this desert preserve, chronicling thousands of years of desert living. A scenic drive, wilderness hike or a night of camping will expose you to a living desert that thrives.