This is an "intermediate" hike being led by the San Diego Natural History Museum Canyoneers. It should be of interest to San Diego Day Hikers. It's in an area not usually open to the public.
Here are some details from the museum website:
Walk Rating: Moderate, 7 miles up to 1500 ft elevation change
Canyoneers have permission to guide at this SDSU field station for this date only. This hike has it all, follow the path to the gorge through riparian and oak woodland habitats along Stone Creek and down to the Santa Margarita river. The trail climbs through steep areas in open chaparral.
The hike begins at 9:00 AM at the rather isolated field station (Thomas 998 C3, N[masked] W[masked]). It should end about 2:00 PM.
Wear good hiking shoes or boots and take water and a light lunch or snack.
Directions: (Fallbrook) From I-15 exit west on Mission Rd. (S13) and turn right onto Willow Glen Rd. Drive to the end of Willow Glen and continue right (north) on Stage Coach Lane. The gate to the reserve will be open a half-hour before the hike. Follow the Canyoneer sign to the parking area. No facilities. Allow 1.5 hours driving time. (Map 998-C3)
For more information visit the Canyoneer hikes page at www.sdnhm.org/education/naturalists-of-all-ages/canyoneer-hikes