The memorial, built in 1962, is visited by more than one million people annually. Accessible only by boat, it straddles the sunken hull of the battleship without touching it. Historical information about the attack, shuttle boats to and from the memorial, and general visitor services are available at the associated USS Arizona Memorial Visitor Center, which opened in 1980 and is operated by the National Park Service. The sunken remains of the battleship were declared a National Historic Landmark on 5 May 1989.