Nestled in a rural neighborhood in Riverside, the Mockingbird Canyon pictographs are a hidden gem. Believed to be the work of the native Luiseno indians, an impressive set of San Luis Rey style polychrome pictographs are on the ceiling of a granite rock shelter. The circles, nets and lines are thought to represent the night sky and the Milky Way.
David Whitley offers his opinions on this fantastic site in his book (see link).
The shelter itself overlooks an intermittent creek where there was once a small village. Some mortars and grinding slicks can still be found along the creek.
The pictographs are fenced to help protect them.