Northwest of Santa Cruz, the 18,000 acre Big Basin State Park has mountain biking is only permitted on dirt roads, including the six mile stretch of Canyon Road, which meanders along Waddell Creek.
The Big Basin Redwoods State Park is home to the largest continuous stand of Ancient Coast Redwoods south of San Francisco, with old growth and recovering Redwood Forest, mixed conifers, oaks, chaparral, and riparian habitats.
The Waddell Creek - Rancho Del Oso area offers a variety of recreational opportunities. The Waddell Creek - Rancho Del Oso entrance for this area is 16 miles north of Santa Cruz via US1 across from Waddell Beach. The main park entrance is 25 miles northwest of Santa Cruz via Highways 9 and 236 and about 65 miles south of San Francisco. All roads into Big Basin are curvy.
Get ready for foggy and damp near the ocean and sunny, warm ridgetops (2,000). The park has a surprising number of waterfalls, a wide variety of environments (from lush canyon bottoms to sparse chaparral-covered slopes, many animals (deer, raccoons, an occasional bobcat) and lots of bird life-- including Steller's jays, egrets, herons and California woodpeckers.
Overall, Big Basin Redwoods State Park is the 77th most popular mountain bike trail of all 132 mountain biking rides in California.