BOSTON (AP) -- The Coast Guard says a fog signal cannon at Boston Harbor Light Station on Little Brewster Island is the military branch's oldest artifact.
Officials recognized the cannon's history Friday by presenting a citation to the lighthouse keeper.
Coast Guard officials say the 293-year-old cannon once fired every half-hour during times of poor visibility.
It helped steer ships clear of the island and its surrounding shoals.
In the 1960s, authorities retired the cannon to the U.S. Coast Guard Academy in New London, Conn.
But Coast Guard officials returned it to Boston Harbor Light in 1993 as a way to recognize the history of America's first light station.