Pebble-covered Cross Rock Beach is so tiny that it sometimes remains underwater until late summer. The beach path is so steep and dangerous that "you shouldn't even think about using it," says Red Rock regular Hugh Fullerton, who estimates the trail's angle at 45 degrees. At least one person has fallen from the cliffs.
Legal status: Unknown, believed to be part of Mount Tamalpais State Park.
How to find it: Follow directions for Muir Beach. Between the Step Ravine Campground sign (about four miles north of Muir) and the big Red Rock parking lot (a mile south of Stinson Beach), look for cars pulled over next to Highway 1. Park there and then walk down the path to the beach.
The beach: The beach is pebbly, with a thin ribbon of sand only in late summer and fall.
The crowd: It may or may not be deserted. When nearby Red Rock is crowded, Cross Rock sometimes gets a few visitors.
Problems: Rocky shoreline; extremely dangerous trail; no access in winter, spring, or early summer; unknown legal status.