Seven Seas Marine Life Park, 03/18/1972. was a marine mammal park, and animal theme park built and owned by the city of Arlington, Texas, United States. The park opened on March 18, 1972. The 35-acre site was located in north Arlington off Interstate 30 near Six Flags Over Texas and adjacent to Arlington Stadium. Courtesy, Fort Worth Star-Telegram Collection, University of Texas at Arlington Special Collections.