The siege of Leningrad (Блокада Ленинграда; Leningrader Blockade; Leningradin piiritys) was a prolonged military blockade undertaken by the Axis powers against the Soviet city of Leningrad (present-day Saint Petersburg) on the Eastern Front of World War II. Germany's Army Group North advanced from the south, while the German-allied Finnish army invaded from the north and completed the ring around the city. The siege began on 8 September 1941, when the Wehrmacht severed the last road to the city. Although Soviet forces managed to open a narrow land corridor to the city on 18 January 1943, the Red Army did not lift the siege until 27 January 1944, 872 days after it began. The blockade became one of the longest and most destructive sieges in history, and it was possibly the costliest siege in history due to the number of casualties which were suffered throughout its duration. An estimated 1.5 million people died as a result of the siege. While not classified as a war crime at the time, in the 21st century, some historians have classified it as a genocide due to the systematic starvation and intentional destruction of the city's civilian population. Leningrad's capture was one of three strategic goals in the German Operation Barbarossa and the main target of Army Group North. The strategy was motivated by Leningrad's political status as the former capital of Russia and the symbolic capital of the Russian Revolution and Bolshevism hated by the Nazi Party, the city's military importance as a main base of the Soviet Baltic Fleet, and its industrial strength, including its numerous arms factories. In 1939, the city was responsible for 11% of all Soviet industrial output. It has been said that Adolf Hitler was so confident of capturing Leningrad that he had invitations printed to the victory celebrations to be held in the city's Hotel Astoria. Although various theories have been put forward about Germany's plans for Leningrad, including making it the capital of the new Ingermanland province of the Reich in Generalplan Ost, it is clear Hitler intended to utterly destroy the city and its population.