Circle Line X was originally built for the
United States Navy in 1944 as a
Landing Craft Infantry (Large), designated USS
LCI(L)-758. She was manufactured at the
Commercial Iron shipyard in
Portland, Oregon, which produced more than 200 ships for
World War II. During the war, she traveled an estimated , and none of her crew died during battle. The
758 is cited as having shot down two enemy aircraft and participated in five battles. These military engagements earned
758 and her crew numerous awards, she was originally known as
Circle Line Sightseer X and later just as
Circle Line X. She was one of several ex-LCI vessels acquired by Circle Line, Although
Circle Line X was slower and harder to maneuver than Circle Line's other fleet, two of the ship's captains said that she "became one of our favorites". Like the other Circle Line fleet,
Circle Line X was used on the company's cruises that circumnavigated Manhattan, except during the winter, when she was stored in Mill Basin. and the filming of an episode of the TV series
Zero Hour, where the wheelhouse stood in for a submarine's interior.
The New York Times wrote that many of the crew members were unaware that she still existed and that, at the time, the vessel had various printouts describing her naval history.
Circle Line X was nominated for inclusion on the
National Register of Historic Places and the
New York State Register of Historic Places that year. According to the NRHP nomination report, the vessel retained almost all of her sightseeing-era features, but few remnants of her military use were intact. == Description ==