BOSTON (AP) — The U.S. Postal Service has introduced a stamp commemorating the world's oldest commissioned warship that's still afloat.

On Saturday morning, postal officials unveiled the USS Constitution forever stamp at the Charlestown Navy Yard in Boston.

The stamp is the first in what officials say will be a stamp series commemorating the bicentennial of the War of 1812.

Nicknamed "Old Ironsides," the ship was first launched in 1797.

On Sunday, the ship will be tugged from its Boston Harbor berth.

Then it will sail on the open seas for a 10-minute cruise to mark the battle against the British that won the ship its nickname.

The stamp image is based on a painting that Michele Felice Corne did of the vessel around 1803.