Arch Canyon Trail

Approximately equidistant from the cities of Tucson and Phoenix lies Organ Pipe Cactus National Monument, a park that abuts the border of the United States and Mexico. The park was set aside to protect the rare cactus for which it was named, and hundreds of miles of trails wind through the arid landscape.

One of those trails is the Arch Canyon Trail. The official listing for the trail is only 1.2 miles, which takes visitors briefly into a beautiful canyon which the arch overlooks. However, intrepid climbers have taken things into their own hands and fashioned a trail up a near-vertical cliff to get to the arches themselves. A steep, rocky 2.4-mile hike (more of a climb, really) leads to a set of natural arches and stunning views of Organ Pipe Cactus National Monument, Arizona, and Mexico.

The only clue that this trail exists is a sign that reads, ominously, "CAUTION: STEEP ROCKY ROUTE AHEAD." Heed the sign's warnings, and carry a first aid kit and plenty of water if you choose to find your way to the arches.