Arizona Trail

A diagonal crossing of Arizona, this National Scenic Trail runs about 800 miles from the Mexican border to Utah, climbing from Sonoran desert through pine-clad sky islands and across the Grand Canyon rim to rim.

A thru-hike takes six weeks or more, ranging from near desert lowlands to around 9,600 feet in the mountains, with the canyon crossing a dramatic centerpiece. The trail divides into 43 numbered passages, many of them fine day and section hikes in their own right.

Practical detail: no single permit covers the route, though a backcountry permit is needed to camp below the Grand Canyon rims, and water planning is the defining challenge across the arid stretches. Cached and piped sources are used carefully, and heat dictates timing.

Spring and fall are the sensible windows, with March to May favored for northbound hikers chasing mild desert temperatures before summer, and autumn good for the reverse. Completed in 2011, the trail showcases the state's remarkable range of ecosystems in a single continuous line.