SeaWorld San Diego is an animal theme park, oceanarium, outside aquarium and marine mammal park, in San Diego, California, United States, inside Mission Bay Park. It is owned and operated by SeaWorld Parks & Entertainment.
SeaWorld was founded on March 21, 1964 by four graduates of the University of California, Los Angeles. Although their original idea of an underwater restaurant was not feasible at the time, the idea was expanded into a 22-acre (8.9 ha) marine zoological park along the shore of Mission Bay in San Diego. After an investment of about $1.5 million, the park opened with 45 employees, several dolphins, sea lions and two seawater aquariums, and hosted more than 400,000 visitors in its first year of operation.