Witness fault action in freeze-frame at Devils Punchbowl Natural Area in Los Angeles County.

Tens of millions of years in the making, Devil's Punchbowl is certainly Los Angeles County's most spectacular geological showplace. When looking down into this 300-foot-deep chasm, you sense the enormity of the slow yet inexorable forces that fashioned the tilted, tangled collection of beige sandstone slabs.

The Punchbowl is caught between two active faults -- the main San Andreas Fault and an offshoot, the Punchbowl Fault -- along which old sedimentary formations have been pushed upward and crumpled downward, as well as transported horizontally. Erosion has put the final touches on the scene, roughing out the bowl-shaped gorge of Punchbowl Canyon and carving, in many unique ways, the rocks exposed at the surface.

A hike of six miles round trip is required to reach the best view spot -- "Devil's Chair," a fenced viewpoint at the upper rim of the Punchbowl. You can start this hike at Devil's Punchbowl Natural Area, which is seven miles southeast of the Mojave Desert community of Pearblossom. At Pearblossom turn south on Longview Road and continue on Route N6, following signs to the natural area, which contains a fine nature center and a network of short trails. Recent snowfall may have blanketed the trail that ascends to the Devil's Chair, so check with Devil's Punchbowl rangers (661-944-2743) about trail conditions if you plan to visit during the next couple of weeks.

From the south side of the parking lot at Devil's Punchbowl Natural Area, find and follow the signed Burkhart Trail as it climbs northwest along the rim of the punchbowl. You're actually following the upper (south) edge of a downward-sloping terrace -- part of an alluvial fan left high and dry when the Punchbowl creek began carving a new course northeast. You join an old road at 0.5 mile, pass a small reservoir at 0.7 mile, and arrive at a trail junction at 0.8 mile. Here, in a Coulter-pine grove, bear left on the Punchbowl Trail leading east. The delightful, contouring path takes you around several shady ravines, all draining into the Punchbowl. After some sharply descending switchbacks, you reach a trail junction (3.0 miles) from where a 0.1-mile spur goes west and then north over a narrow, rock-ribbed ridge to the high perch known as Devil's Chair. Protective fencing furnishes some psychological comfort for the nervous-making traverse.

Another approach to Devil's Chair is possible from the east via South Fork Campground. This approach entails a crossing of the South Fork creek, which may be problematical through the spring season due to fast-flowing water.