The Santa Monica Mountains are traversed by one of the world's busiest freeways, the 405, on the east side; crowned by the 101Freeway on the north and west side; and you'll find Highway 1 also called the Pacific Coast Highway or PCH on the southern ocean boarder.
Mulholland Scenic Corridor (Mulholland Highway) winds its way through the recreation area offering views of canyons, valleys, and the ocean. The route is legendary among motorcyclists and other driving enthusiasts who enjoy the challenge of the curvey roadway, so exercise extreme caution on blind turns.
TANN Traffic provides information about real time traffic in the Los Angeles area.
California's Department of Transportation (CALTRANS) has information on road closures and conditions.