U-505, German submarine museum at Museum of Science and Industry, Chicago, United States

U-505 is a German military submarine from World War II permanently displayed at the Museum of Science and Industry in Chicago. The vessel sits in a specially built indoor space with direct access to cargo holds, torpedo tubes, and engine rooms across multiple decks.

The US Navy took possession of the vessel on June 4, 1944, off the coast of West Africa after it was cornered by the escort carrier group around USS Guadalcanal. After the war ended, it was used for research purposes before being moved to Chicago in 1954 and opened to the public.

The "U" in U-505 stands for Unterseeboot, Germany's term for a submarine, and the number is its Kriegsmarine hull number. The boat's tower emblem under her first commander, Axel-Olaf Loewe, was a leaping lion holding an axe, and her sponsor town was Schliersee in Upper Bavaria. Visitors today see the vessel as a war memorial at the Museum of Science and Industry.

Access is through separate guided tours included with museum admission that allow visitors to walk through the interior spaces. The passageways are narrow and require ducking at several points, so comfortable clothing is advisable.

When American sailors boarded, they found the Enigma cipher machine and related codebooks still aboard before the German crew could destroy them. These materials remained secret during the war and helped Allied forces decode encrypted messages from the German navy.