The U.S. Lightship Service was started in 1820. Like lighthouses and buoys, lightships were navigational aids. The lights atop their masts were similar to those in lighthouses, but their portability made them much more versatile.
The Lightship Portsmouth was laid down on March 6, 1915, launching the following January and fully commissioned as Lightship LV-101 on September 2, 1916. She served for 48 years off the coasts of Virginia, Delaware and Massachusetts helping mariners avoid dangerous shoals or enter safely into harbors at night. Typically, the ship would anchor at a strategic location at sea and remain there for months at a time. The maximum crew for the Lightship PORTSMOUTH during her half-century in service was 15 men.
In 1964, she was retired to Portsmouth, Virginia and renamed according to the custom of naming lightships after the site where they are stationed.
In 1989, the Lightship PORTSMOUTH was designated a National Historic Landmark. Now a museum, the ship’s main deck has been realistically populated with artifacts, uniforms, photographs, and more to show a day in the life of a lightship sailor.