"Hikers in Southern California," writes Karen Berger in Hiking the Triple Crown; How to Hike America's Longest Trails, "invariably talk about hiking through the desert. Technically, that's not exactly true. While the trail does cross some of Southern California's desert valleys, for the most part it stays high and dry on chaparral-covered slopes. But from a hiker's point of view, one thing is true of almost all of Southern California: For 700 miles, there is too much sun and too little water."

The PCT departs from the Mexican border near the small town of Campo (elev. 2,600'). In May (when most thru-hikers and riders begin their journey north) temperatures often reach the 90s in this region. Over the course of the next 40 miles, the trail passes through Lake Morena County Park, beneath Interstate 8, and then climbs through chaparral, scrub oaks, and pines to the rim of the Jeffrey pine-shaded Laguna Mountains. In the Lagunas temperatures in May can dip below freezing.

Next the trail dips into Anza-Borrego Desert State Park at Scissors Crossing, and then winds up, down, and around the San Felipe Hills and lesser mountains of the Cleveland National Forest before crossing Highway 74 at 4,900' and climbing the backbone of the San Jacinto Mountains. Here it reaches its highest point in this section at 9,030' shortly before it plunges to its lowest, crossing beneath Interstate 10 at (elev. 1,190') in broad San Gorgonio Pass.

From here, the PCT climbs steeply to the crest of two east/west-oriented ranges, often under welcome forest shade. It passes near Big Bear Lake and Lake Arrowhead before crossing Interstate 15 between the San Bernardino and San Gabriel Mountains at Cajon Pass near Silverwood Lake State Recreation Area. The vistas from the trail in these mountains include the Los Angeles Basin and Mojave Desert.

To the west of Mt. Baden-Powell and the Angeles Crest National Scenic Byway, the PCT descends to Highway 14 at Agua Dulce, then traverses the often brushy landscape of the Sierra Pelona. It continues north for a generally hot and dry traverse across the San Andreas Fault Zone and western arm of the Mojave Desert before climbing into the Tehachapi Mountains where it crosses Highway 58 and enters the Sierra Nevada. The southern California section ends where the trail crosses Highway 178 at Walker Pass (elev. 5,246').

For thru-hikers and riders, the most important considerations when along the Southern California PCT are water and hot temperatures (ranging from the 80s to the 100s). Springs and seasonal water sources begin to dry up in April or May and distances between reliable water can be long (8 to 20 miles). For help finding water, refer to the PCT guidebooks, which tend to give accurate accounts of water sources and their reliability, but remember -- conditions do vary from year to year. Other challenges in Southern California include flies, poison oak and rattlesnakes.