Malibu Lagoon State Beach is a state protected beach of California, United States, and a unit of the Santa Monica Mountains National Recreation Area. Also known as Surfrider Beach, it has a long-standing reputation as a premier surfing beach. Located in Malibu, California, it was dedicated as the first World Surfing Reserve on October 9, 2010. The 110-acre site was established as a California state park in 1951.