Touring * Fitness * Artistic *

From U.S. 101 in Menlo Park, take the Marsh Road exit and proceed one block northeast to park at Bayfront Park.

The Dumbarton is the only bridge you can skate on that crosses the San Francisco Bay. If you have the skills, it's worth a once-only trip on a clear day just to stop at the top of the bridge and enjoy the view. A good starting point is Bayfront Park, a former landfill on the edge of the bay that has been converted into an attractive park. For the purposes of touring, skating within the park is limited to a half mile of paved roads. (The trails that head up into the landfill-created hills are paved, but unfortunately, they're covered with loose gravel, and the surface is too slippery for skating.)

The Bayfront Trail starts at the entrance to the park and extends southeast along Bayfront Expressway. It can be quite windy out here, and the return is usually against the wind, so plan accordingly. The first mile or so of the trail has a fairly rough surface, though the quality does improve further on. Just before it reaches Willow Road a mile and a half from the Bayfront Park entrance, the trail makes a sharp left to follow the edge of the bay around the Sun Microsystems "campus." Skate around Sun (and its tempting parking lots) to University Avenue.

Strong skaters ready for a mile-long climb and narrow return descent can continue to the Dumbarton Bridge by crossing Bayfront Expressway at the University Avenue stoplight. The trail continues east toward the bay and is almost totally flat until you reach the bridge, where it climbs fairly steeply to the top of the arc. Here you'll be skating on a path separated from the roadway by a low barrier. This may be unnerving for lower-level skaters, since the bridge traffic is fast, close, and noisy.

From the center of the bridge on a clear day, you can see most of the Bay Area shoreline communities, including Foster City, Oakland, San Francisco, and Palo Alto. Just to the south is an old railroad bridge (unused) and the suspended pipeline of the Hetch Hetchy Aqueduct, which brings water from the Sierra Nevada. If you're ready for more adventure, you can continue skating all the way to the East Bay (see the Wildlife Refuge/Dumbarton Bridge tour link below), or return the way you came. Be very careful to control your speed when descending the bridge. Since there's no room to make slalom turns, a thick brake pad and good heel braking skills are a must.

• Wildlife Refuge/Dumbarton Bridge