At 9.51pm on Tuesday, 13 February 1945, Dresden's air-raid sirens sounded as they had done many times in the previous five years, until then most always a false alarm. No searchlights probed the skies above the unprotected target city; the guns had mostly been moved East to counter the Russian advance. By the next morning, 796 RAF Lancasters and 311 USAAF Flying Fortresses had dropped more than 4,500 tons of high explosives and incendiary devices. More than 25,000 inhabitants perished in the terrifying firestorm, and thirteen square miles of the city's historic centre, including incalculable quantities of treasure and works of art, lay in ruins. It was Ash Wednesday 1945. This is the first serious re-appraisal of an event that lives in the popular memory with Guernica and Hiroshima as a by-word for the horror of twentieth-century air warfare. Drawing on archives and primary sources only accessible since the fall of the East German regime, together with British and American records, Frederick Taylor has also talked to Allied aircrew and the city's survivors, whether Jews working as slave labourers, members of the German armed services, refugees, or ordinary citizens of Dresden.