Marine World, Former amusement park in Redwood City, San Mateo County, California, US

Marine World was an amusement park in Redwood City, San Mateo County, California, that operated from 1968 to 1986. Built on reclaimed land, it offered animal shows, a jungle-themed theater, and safari-style attractions across a large outdoor site.

The park opened in 1968 under the ownership of the American Broadcasting Company, built on land that had previously been water. In 1972 animal trainer Ralph Helfer took over and renamed it Marine World/Africa USA, adding more wildlife features before the park eventually moved to Vallejo in 1986.

The park's name changed to Marine World/Africa USA after animal trainer Ralph Helfer took over in 1972, and the site combined marine displays with African wildlife. It stood beside Central Lake in Redwood City, on flat ground about 2 metres above sea level, with Belmont Hill rising 2.5 km to the north.

Marine World no longer exists, as the Redwood City site is now occupied by the headquarters of Oracle Corporation. Those curious about the park's history can find information through local archives and old photographs rather than on-site.

The park was built on land that had previously been submerged, making the construction of such a large outdoor attraction on that site an unusual feat for the time. Today the grounds show no trace of the former park, as they were fully transformed into a tech company campus.