After paying a small entrance fee, head northwest on a level, paved path, passing an information board with history of the park and of the redwood-conservation movement. This path is commonly called the Main Trail, but it is also the continuation of the Bootjack Trail from Mt. Tamalpais State Park.

      About 100 feet from the trailhead, you pass a path, right, to the gift shop and the cafe, which are open 9 A.M. to 5 P.M. Redwood Creek, which gathers water from several tributaries cascading down the south side of Mt. Tamalpais, is on your left.

      Approaching Bridge 1, you get your first look at the giant coast redwoods that fill the valley, making this such a special place. Beyond Bridge 1, you stay on the east side of Redwood Creek. Rest benches here and there invite you to sit and contemplate the sights and sounds of this ancient forest, which, on weekends, may be full of visitors. On a quiet, fog-shrouded mornings, however, your only companions may be feathered ones. About 70 species of birds, including the secretive spotted owl, have been observed in Muir Woods.

      A junction with the Ocean View Trail, right, serves as a meeting place for ranger-led walks; times for these are posted near the entrance station. Continuing straight, you enter a realm dominated by giants. Dense stands of redwoods create a shady environment suited to only certain other types of plants, and the thick carpet of needles and twigs deposited each winter, called duff, makes it hard for seeds to sprout. Coast redwoods are often joined by other plants suited to the damp, shady environment. Among these are California bay, tanbark oak, hazelnut, thimbleberry, evergreen huckleberry, and western sword fern.

      When you reach Bridge 2, where a vending machine has maps for sale, look across the creek: there stands the monument’s tallest tree — 253 feet — and, at 13 feet in diameter, its most stout. Stay on the east side of the creek for now; you’ll visit the west side later. Beyond the bridge, the canyon holding Redwood Creek narrows, with steep hillsides rising both left and right.

      Fallen Giant

      Near the end of your hike, when you reach a fallen tree, sawed to clear a path for the trail, take a minute to imagine yourself nearby on April 6, 1993, when this 419-year-old giant, its roots loosened by winter rains, came crashing down. Actually, the tree had begun to lean several centuries ago, but it responded by growing more wood on the supporting side. Thus its cross-section is an oval instead of a circle.

      Redwood Creek

      Redwood Creek has runs of coho salmon and steelhead trout, both listed as threatened species under federal law. Channeled in the 1930s to prevent flooding, the creek is now being allowed to resume its winding course.

      Passing Bridge 3, left, you enter Cathedral Grove, where the path divides around this fantastic stand of trees. Here, on May 19, 1945, delegates who came to San Francisco to form the United Nations met to honor Franklin Roosevelt, who had just died. Some of the trees here show scars from fire; others have large, grotesque lumps called burls.

      The coast redwood, a species that first appeared some 250 million years ago, has developed strategies to withstand natural disasters, including fire. These include thick, insulating bark, and sprouting from burls, or clusters of dormant buds.

      Passing the Fern Creek Trail, right, you cross a stone bridge over Fern Creek, and then, in a couple of hundred feet, pass the Camp Eastwood Trail, right. Several hundred yards ahead, your path curves left, and a single-track trail, the Bootjack Trail, heads right, into Mt. Tamalpais State Park. After about 100 feet, you come to Bridge 4, which takes you across Redwood Creek.

      Climb moderately on the rocky trail to a T-junction, where you turn left on the Hillside Trail and continue to climb, aided now by wooden steps. The grade soon eases, and you follow a narrow trail, sliced from a steep hillside, into a ravine that holds a tributary of Redwood Creek. After crossing a plank bridge, the route swings sharply left, finds a short stretch of level ground, and then descends on a gentle grade.

      In places, parts of the complex, but shallow, root system underlying a redwood-forest floor are exposed. Redwoods lack a main tap root, and instead stabilize themselves by interlocking their roots with those of other trees.

      Your route stays well above Redwood Creek, in places squeezing between two or more giant trees, then descends to a four-way junction and, just beyond it, Bridge 2. Here you turn right, staying on the west side of the creek and walking through Bohemian Grove, another stand of extraordinary trees, some of them fire-scarred. Fire is part of the natural cycle, and is often beneficial. The National Park Service now recognizes the importance of fire and since 1997 has conducted prescribed burns in Muir Woods.

      At Bridge 1 the route crosses the creek and closes the loop. Here you turn right and retrace your route to the parking area.

      TRIP 10 Muir Woods National Monument: Tourist Club

      HIGHLIGHTS This loop, which uses the Main, Fern Creek,