USS Constitution ("Old Ironsides")

USS Constitution was launched in 1797 and is the world's oldest commissioned naval vessel still afloat. She earned the nickname "Old Ironsides" during the War of 1812 after witnesses reported British cannonballs appearing to bounce off her oak hull. The ship is berthed at the Charlestown Navy Yard and is part of the Boston National Historical Park, where visitors can tour the vessel and related exhibits.