This boat under a tarp is the Swiftsure Lightship. A lightship is a boat that serves the purpose of a lighthouse, often used in places where a lighthouse cannot be built or if they just need a temporary light beacon. Lightships also tend to be less costly than lighthouses. The Swiftsure's light beacon can be found at the top of her stern mast.

The Swiftsure was one of a few lightships that could run under her own power while most would have to be towed to other places. Built in 1904 and numbered LV-83 she was in service serving at all 5 of the United States Coast Guard's west coast lightship stations, she remained in service until 1960. She is the oldest American lightship still in existence and is the only one that still retains her original engines and equipment.

6 years after she was decommissioned, the Swiftsure was purchased by the Northwest Seaport for preservation. Today she is docked between the S.T. Arthur Foss and the Nuwamish Fire Ship on Lake Union.