John Paul Jones is an important man in the history of the US Navy and is considered the father of the USN (although it was actually started by none other than George Washington).
Though his naval career never rose above the rank of Captain in the Continental Navy after his victory over the Serapis with the frigate Bonhomme Richard, John Paul Jones remains the first genuine American Naval hero, and a highly regarded battle commander. His later service in the Russian Navy as an admiral showed the mark of genius that enabled him to defeat the Serapis.
This very elaborate crypt, which contains his remains is located under the main dome of the cathedral at the USNA.