It's hard to explain the feeling you get in the old-growth forests of Redwood National and State Parks. Everything seems big, misty, and primeval -- flowering bushes cover the ground, 10-foot-tall ferns line the creeks, and the smells are rich and musty. It''s so Jurassic Park, you half expect to turn the corner and see a dinosaur.

The scientific name for these massive conifers is Sequoia sempervirens, cousins of the giant sequoias. Sheathed in rough reddish bark, miraculously fire-resistant, their stout straight trunks shoot up 100 feet or more before a canopy of branches begins; they often reach a total height of more than 300 feet. Among the planet''s most ancient individuals -- the oldest dated coast redwood is more than 2,200 years old -- they only grow in temperate rainforests, meaning nowhere but the U.S. Pacific Coast. In 1968, the federal government created Redwood National Park (nowadays combined with three state redwood parks) to protect what''s left of this seriously endangered species. The relative isolation of this stretch of coast helped the forests survive intact, but it also makes for a long drive.

The most spectacular display is along the Avenue of the Giants, a 31-mile stretch of U.S. 101 through the Humboldt Redwoods State Park (tel. 707/946-2263; www.humboldtredwoods.org). Environmentalists bemoan the tacky attractions along this route, but youngsters love 'em -- from south to north, hollow Chimney Tree, where J.R.R. Tolkien's Hobbit is rumored to live; One-Log House, a small dwelling built inside a log; and the Shrine Drive-Thru Tree. More dignified landmarks include Founders Grove, honoring those who started the Save the Redwoods League in 1918; and the 950-year-old Immortal Tree. Don't settle for looking at all this out your car window -- from many parking areas you can ramble on short loop trails into awesome redwood groves.

The other cluster of parks begins another 100 miles or so farther north, threaded along U.S. Hwy. 101: Redwood National and State Park. The most scenic drive parallels 101, along the Newton B. Drury Scenic Parkway, passing through redwood groves and meadows where Roosevelt elk graze, and Coastal Drive, which has grand views of the Pacific. But again, the truly spine-tingling experience requires getting out and hiking through these soaring perpendicular woods. Pick up a park map to find your way to Tall Trees Trail, a 3 1/4-mile round-trip to a 600-year-old tree often touted as the world's tallest (get a permit at the NPS site a day in advance); the self-guided mile-long Lady Bird Johnson Grove Loop; the short, very popular Fern Canyon Trail (advance permit required); or, for the littlest hikers, the .25-mile-long Big Tree Trail, a paved trail leading to -- what else? -- a big tree.

Nearest Airport: Del Norte County Regional, Crescent City.