The USS Constitution fired off a 21-gun salute  to commemorate Presidents Day Monday.

The traditional blasts from the canons on board the world’s oldest commissioned oldest warship, sounded off at noon. President George Washington, whose birthday Presidents Day celebrates, named the ship after the document that defines our nation.

The  USS Constitution, nicknamed Old Ironsides, played a vital role in the Barbary Wars and the War of 1812, safeguarding American sea lanes from 1797 to 1855.

The warship is open for free public visitation Wednesday through Sundays, from 10 a.m. to 4 p.m. All guests 18 and older must present a valid state- or federally-issued photo ID or passport to board.