USS Constitution was launched in October of 1797. It is the the oldest commissioned ship afloat in the world and is still in service in the US Navy. 
Constitution was built at Edmund Hartt’s shipyard in Boston, Massachusetts from the resilient lumber of 2,000 live oak trees. Its planks were up to seven inches (178 mm) thick. The ship’s design was also unique for its time because of a diagonal cross-bracing of the ship’s skeleton that contributed considerably to the ship’s structural strength.
In 1812, USS Constitution met the frigate HMS Guerriere off the coast of Nova Scotia. The British ship fired the first shot of the battle; 20 minutes later, Guerriere was a dismasted hulk, so badly damaged that she was not worth towing to port. Hull had used his heavier broadsides and his ship’s superior sailing ability, while the British, to their astonishment, saw that their shot seemed to rebound harmlessly off Constitution’s strong live oak hull—giving her the nickname “Old Ironsides”.
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