Backbone Trail from Circle X Sandstone Peak Parking Lot (mile marker 6.37 on Yerba Buena Rd.) to Yerba Buena Rd (mile marker 9.10)
- Mileage: 5.5 miles
- Agencies: NPS
- Flora: Chaparral and meadows.
- History: Circle X was formerly a boy scout camp run by the Los Angeles Exchange Club, a business men's club with the symbol of a circle and an x, thus the name Circle X.
- Cautions: Use the connector from the Sandstone Peak parking area to the Mishe Mokwa trail parking on Yerba Buena Rd (mile marker 7.0). Cross Yerba Buena Rd to the larger parking lot. The trail continues at the lower portion of the parking lot. This section of the trail is a multi-use trail and is open to all users. Bikes yield to hikers & horses, hikers yield to horses. The trail ends at Yerba Buena Rd (mile marker 9.10).
There is an interruption of the Backbone Trail from Yerba Buena Road mile marker 9.10 until you reach Mulholland Highway. The last half of the interrupted section has been constructed and is open from Mulholland, but there is no easement for the section across the Etz Meloy motorway. Do not cross this section. Sensitive negotiations on this easement are taking place now.