Zitadelle

Zitadelle ("Citadel") may refer to:
 * Spandau Citadel (German: Zitadelle Spandau), a fortress in Berlin
 * Zitadelle (Berlin U-Bahn), a railway station serving the Spandau Citadel
 * Zitadelle Mainz, a fortress in Mainz
 * Operation Zitadelle, the German offensive operation for the Battle of Kursk