Natural Bridges can be accessed from Parrotts Ferry road. It is open to foot traffic only and is a somewhat steep trail down to Coyote Creek. In the summer bring your inner tube to float down the river and under the cave like natural bridge.
Other trails in the area: Carson Creek, Gold Rush, Frontier, Peoria Wildlife Mountain and Ridge Trail (Horses allowed), and Table Mountain.
New Melones Visitors Center
Hours: Open year round Wednesday through Sunday, 10:00 a.m. to 4:00 p.m., and closed Mondays and Tuesdays
6850 Stud Horse Flat Road
Sonora, CA 95370
New Melones Lake Visitor Center and Museum were completed as a part of the New Melones project in 1992. The modern displays and exhibits are about the area’s geologic past, Mi-Wok Indian and early human history, the California Gold Rush, mining techniques, ranching, the town of Robinson Ferry, natural history, and the New Melones project itself. Highly recommended are the guided history and nature walks that rangers conduct.
There is more information about New Melones Lake here.