Principal photography took place from September to November 2003, on location in Berlin, Munich, and in Saint Petersburg, Russia. As the film is set in and around the "Führerbunker", Hirschbiegel used eyewitness accounts, survivors' memoirs, and other historical sources during production to reconstruct the look and atmosphere of 1940s Berlin. The screenplay was based on the books "Inside Hitler's Bunker" by historian Joachim Fest and "Until the Final Hour" by Traudl Junge, one of Hitler's secretaries, among other accounts of the period.