USS Constitution, also known as Old Ironsides, is a wooden-hulled, three-masted 44 gun, heavy frigate of the United States Navy. She is the world’s oldest commissioned naval vessel still afloat.[Note 1] She was launched in 1797, one of six original frigates authorized for construction by the Naval Act of 1794 and the third constructed. Serving in the Barbary Pirate wars and the war of 1812, she resisted damage thus her nickname âOld Ironsidesâ. rochestermilitary.com