Outlaw’s Lair : Famed movie backdrop Vasquez Rocks, named for a stagecoach robber, is really a geological treasure house.

Vasquez Rocks County Park is believed to be the only park in the United States named for an outlaw--the 19th-Century cattle rustler and stagecoach robber Tiburcio Vasquez, who was hanged for murder in 1875. Vasquez and his gang used the rocks as a hideout long enough to endow the area with the legend and mystique of his name.

From the earliest days of motion pictures, the rocks have also been used for movie backgrounds, featured in nearly every TV Western, and in countless space-picture settings for both television and movie dramas. Recently, Vasquez Rocks was used for the filming of “Star Trek” and for the feature film “The Flintstones.”

The park is roughly 35 miles from North Hollywood, up the Antelope Valley Freeway to the Agua Dulce Canyon Road exit.

Follow Escondido Canyon Road north (under the freeway) for about two miles to the rocks.

Either drive (there’s a $2 charge for vehicles) or walk in, and begin a walking tour of a 750-acre expanse of jagged, soaring rock formations that have an impact unlike any other.

The park is really a museum of geological history, with displays of layers of rock, dozens of millions of years old, tilted sideways, jutting into the air, the result of 20 million years of earthquake action, in which ancient rock layers were compressed, then folded and tilted, and, as erosion removed the soil, etched out as huge, jutting slabs.

Noon: Walk the trail from the car parking area to the northeast, past the biggest, most dramatic cliff in the park. As you approach, it looks like a shark’s head, with a peak 60 feet overhead.

This rock, like all the rocks in the park, changes contour completely as seen from different vantage points; sharp angles giving way to soft curves as you reach a different perspective.

12:15 p.m.: Stand at the base of the Big Rock, and prepare to climb. This is the most challenging and exciting ascent of the park, a steep slope of rock that is porous enough to be climbed upright, if you’re wearing rubber-soled shoes and feeling brave. Most people, though, stoop for the climb, some all the way to hands and knees.

12:20 p.m.: Enjoy the summit vista from a narrow precipice, without guardrail, or any protection. Be careful. It’s a nice place to sit and gaze over the strange rockscape, and contemplate the many millions of years it represents.

12:30 p.m.: Go back down the way you came up, using the holes in the rock (the ones that resemble dinosaur footprints) as hand- or footholds. At the base, go right on a trail behind the Big Rock, which takes on the wavy, soft contour of melting snow.

12:45 p.m.: Start the one-third mile nature trail, with plaques identifying native plants such as California sagebrush and juniper. There is abundant European mustard, with cliff swallows circling overhead.

1 p.m.: Start a walk around the back side of the park, away from the noise and crowds at the Big Rock. Climb the first of several rock mesas that form a jagged rim.

1:30 p.m.: Climb the next rocky incline to a high, massive overhang with a view of prehistoric rock formations all the way to the eastern horizon. This is what you came for. Sit, eat a picnic lunch if you brought one, and experience the changing sense of time and space the rock formations give you.

1:45 p.m.: Follow a rugged trail, richly shaded with yucca and juniper, down over a saddle, past a maw of exposed rock strata, the visible underside of geologic activity, the rocks forced upward on a slant by millions of years of sub-strata action. The harsh caws of blackbirds sound like crows. They are probably ravens, a bird native to the rocks.

2 p.m.: Reach another rock summit on which to sit, gaze and ponder, out of sight and sound of people who congregate near the Big Rock. You could be a million years away.

2:15 p.m.: Climb the next rock summit, this one considerably higher than the Big Rock, where the exposed plates of the strata to the east look like the walls of a canyon, sticking out of the ground.

2:30 p.m.: Climb the last promontory on this perimeter tour, a rock summit that gives you a different perspective of the promontories you’ve climbed so far. Red-tailed hawks cry as they ride thermals overhead, and doves sound their mournful cry over the faint whisper of traffic on the the Antelope Valley Freeway a couple of miles to the east.

2:45 p.m.: Start back to the flats at the foot of the Big Rock, where you began climbing. It’s more than a 15-minute walk to the parking area, which gives you time to readjust to the present, and the current geological era.

The park is open every day, sunup to sundown. Admission is free, with a $2 charge for vehicles.