The USS Constellation is a sloop-of-war launched in 1854, the last sail-only warship designed and built by the United States Navy. She served through the Civil War, made a Mediterranean deployment, and later became a training ship before being preserved in Baltimore. She is now moored in the Inner Harbor and open for tours.
The ship gives an excellent sense of what a mid-19th-century American naval vessel looked like and how it operated. You can go below decks, see the gun deck, examine the rigging, and understand the scale and complexity of a sailing warship. The combination with the other Historic Ships vessels — the submarine, the Coast Guard cutter — makes for a comprehensive survey of American naval history from the 1850s to the 1940s.