Hike Anza-Borrego's Rockhouse Canyon to where rock-house ruins sit within a forgotten valley.

Straddling the San Diego: Riverside County line, Rockhouse Canyon and the broad, sloping alluvial basin drained by it -- informally known as Rockhouse Valley -- constitute one of Southern California's truly forgotten places. Not much more than a century ago, Cahuilla Indians carried on a traditional way of life here. After the Indians moved to the nearby Santa Rosa Indian Reservation around 1900, a few hardy prospectors made forays into the area, traveling along centuries-old footpaths. Never has a road penetrated farther than the lower reaches of Rockhouse Canyon. Up in the silent valley itself, you might as well have stepped into a time warp. Only the distant glints and rumbles of high-flying aircraft provide evidence of the modern world.

You'll need several hours to day-hike Rockhouse Canyon as described here. Two or even three days of backpacking suffices to explore the spacious valley lying beyond. Don't forget, even on a day trip, to pack along essentials such as water, food, and extra clothing. Anza-Borrego Desert State Park has jurisdiction over much of the canyon, and you'll have to obtain a parking permit ($5 daily, or $50 annual). For information, call 760-767-4205 or 760-767-5311.

At mile 26.7 on Highway S-22 (north and east of Borrego Springs), turn north on Clark's Well Road. Pavement soon ends and you continue driving on dirt, bearing left at 1.5 miles onto Rockhouse Truck Trail. After 9 miles of often-bumpy dirt-road travel in all, you arrive at a point where roads into Butler and Rockhouse Canyons join. This is the absolute limit for vehicles that are not high-clearance, four-wheel-drive machines. Three more excruciatingly slow miles of driving in the appropriate vehicle will take you to the Rockhouse Truck Trail terminus.

On foot now, walk a half mile to Hidden Spring on the left, a small puddle of stagnant water next to a grove of mesquite bushes. Then the canyon narrows, and over the next 3.5 miles you trudge uphill on soft sand through a narrow gorge flanked in many spots by soaring rock walls.

At a point just south of the San Diego-Riverside County line, you'll come upon a granite dike forming a 20-foot "dry fall" (a waterfall only during rare floods). Huge boulders litter the canyon floor, mute testimony to the power of flash flooding.

Eventually, the canyon broadens and you enter Rockhouse Valley, named for the ruins of some rock houses probably built by miners around a century ago. Follow the main sandy wash up the west side of the valley until you reach the base of a boulder-strewn ridge 0.6 mile northwest of the valley entrance; then go 0.2 mile due north to find the three rock houses, all of which are roofless. They're spaced along a low, elongated ridge with a view of the entire valley. Mud used as mortar still clings to some of the walls. Each house had a cozy fireplace inside.

You've now come nearly 5 miles -- assuming you left your car at the end of the Rockhouse road. If this is to be your turnaround point, you'll find the return to be faster and much easier, assisted by gravity all the way.