High Quality Content by WIKIPEDIA articles! The Little Mermaid: Ariel`s Undersea Adventure (titled Under the Sea: Journey of the Little Mermaid in Florida) is a dark ride attraction based on the film The Little Mermaid, located in Paradise Pier at Disney California Adventure and in Fantasyland at Walt Disney World`s Magic Kingdom. The ride opened on June 3, 2011 at Disney California Adventure, and on December 6, 2012 at Magic Kingdom.