Upper Oso Campground is located in Los Padres National Forest, CA, at the end of a public road. Activities include hiking, fishing, swimming, and biking. Trails lead north to San Rafael, a wilderness, via the Santa Cruz Trail. A wilderness trail via the Aliso loop trail leads to the Sage Hill Group Site. A ranger station is located within 2 miles.
Firewood is sold at the host site and fire rings are provided. Changes in the river level occasionally cause the campground to close in the winter.