The park is bisected by U.S. Route 101, which turns north from the coast at Gaviota, passing through the Gaviota Tunnel and Gaviota Pass, which is actually a deep canyon cut entirely through the southern branch of the Santa Ynez Mountains. Gaviota State Park consists of two units, one on each side of the highway. The western unit includes the beach and associated campground, which receives most of the park's visitors.