Little Mermaid, The: Ariel’s Undersea Adventure Dark ride attraction opening at Disney California Adventure on June 3, 2011. Guests embark in an clam shell Omnimover for a visit to scenes from The Little Mermaid film. The attraction is located in a new elegant Victorian Exposition-style building, featuring an ornate 86-foot-long hand-painted mural. Also, as Under the Sea: Journey of the Little Mermaid, in Fantasyland in the Walt Disney World Magic Kingdom, opening December 6, 2012.