Explore the site of California's first gold rush: L.A. County's Placerita Canyon.

One of California's historic hot spots, Placerita Canyon Park hosted the state's first gold rush (1842), farming, oil exploration, and movie-making. You can contemplate these historical details as you visit the park's superb nature center -- housing exhibits on the history, prehistory, geology, plants, and wildlife of the area -- and take a hike along Placerita Canyon's melodious creek.

The park is easy to reach once you get beyond the L.A. Basin traffic. Head north on the Golden State Freeway (Interstate 5) through the San Fernando Valley, and veer right on the Antelope Valley Freeway (Highway 14). Take the second exit, Placerita Canyon Road, turn right (east), and continue to the park's main gate, open 9 a.m. to 5 p.m. daily.

The park's must-do hike, 3.6 miles out and back, is a leisurely streamside stroll of two hours or less. Begin at the main parking lot near the nature center. Cross a bridge, and pick up the trail heading east up Placerita Canyon's live-oak-shaded floodplain. Down by the grassy banks you'll see wild blackberry vines, lots of willows, and occasionally sycamore, cottonwood, and alder trees. In this current transitional season, you'll see both remnant autumn color and plenty of bright, green vegetation popping up from recent rains.

Eventually, the canyon narrows and becomes a rocky gorge. Soaring walls tell the story of thousands of years of natural erosion, as well as the destructive effects of hydraulic mining, which involved aiming high-pressure water hoses at hillsides to loosen and wash away ores. Used extensively in Northern California during the latter Gold Rush, "hydraulicking" was finally banned in 1884 after catastrophic damages to waterways and farms downstream.

After about a mile you reach a split in the trail. The right fork climbs a little onto the chaparral-clad slopes to the south, while the left branch connects with a trail going up to a parking area on Placerita Canyon Road and then goes upstream along the willow-choked canyon bottom. Follow either branch but take the other during your return leg of the hike.

Using either route you arrive at oak-shaded Walker Ranch Group Campground, which contains the scant remains of early-20th-Century cottages hand-built by settler Frank Walker, his wife, and some of his 12 children. Back by the nature center stands another cabin built by Walker but modified later for use in the television series Hopalong Cassidy.

Make Walker Ranch the turnaround point for the 3.6-mile hike -- or, if your legs aren't complaining, the following options are available: (1) Use the Waterfall Trail, south from Walker Ranch, to reach a small waterfall in maple-dotted Los Pinetos Canyon. (2) From the main parking lot, follow the wheelchair-accessible Heritage Trail west under Placerita Canyon Road to the "Oak of the Golden Dream." According to legend, this is where gold was discovered in 1842 by a herdsman pulling up wild onions for his after-siesta meal. (3) Explore a number of other short "nature trails" departing from the main parking lot and nature center.

Placerita Canyon Park was nearly closed in 2003 due to budget shortfalls. The Santa Monica Mountains Conservancy has temporarily taken over administrative control of the park. To make certain the park is open when you visit, you may call the park's nature center, 661-259-7721, or visit www.placerita.org.