USS 'Constitution', also known as 'Old Ironsides', is a wooden-hulled, three-masted heavy frigate of the United States Navy. She is the world's oldest commissioned naval vessel still afloat. She was launched in 1797, one of six original frigates authorized for construction by the Naval Act of 1794 and the third constructed. The name "Constitution" was among ten names submitted to President George Washington by Secretary of War Timothy Pickering in March of 1795 for the frigates that were to be constructed. Joshua Humphreys designed the frigates to be the young Navy's capital ships, and so 'Constitution' and her sister ships were larger and more heavily armed and built than standard frigates of the period.

'Constitution' is most noted for her actions during the War of 1812 against the United Kingdom, when she captured numerous merchant ships and defeated five British warships: HMS 'Guerriere', 'Java', 'Pictou', 'Cyane', and 'Levant'. The battle with 'Guerriere' earned her the nickname "Old Ironsides" and public adoration that has repeatedly saved her from scrapping.

'Constitution' was retired from active service in 1881 and served as a receiving ship until being designated a museum ship in 1907. In 1934, she completed a three-year, 90-port tour of the nation. She sailed under her own power for her 200th birthday in 1997 (116 years from her retirement), and again in August 2012 to commemorate the 200th anniversary of her victory over 'Guerriere'.

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