The rugged eastern edge of the San Gabriel Mountains contrasts with the urban corridor to the south. Several major highways and the street grid patterns of Covina, Pomona, Ontario, and Fontana are evident in this color infrared photograph. Discernible is a small part of the San Andreas Fault in the northeastern quadrant. Other features include the southwest-flowing Santa Ana River (southeast side of the photograph), the Chino Hills and the Puente Hills (southwest edge of the photograph), and the tributary streams of the San Gabriel River that have cut canyons through the San Gabriel Mountains (northern part of the photograph).