21. Walking around the city, you'll notice many partly empty quarters or strangely missing buildings. It is mostly the consequence of what?
From Quiz Belgrade - Crossroads of Rivers and History
Answer:
Bombardment
Belgrade suffered heavy civilian and infrastructure losses during turbulent 20th Century. During this period, it was heavily bombarded and attacked 6 times. Austrian-Hungarian troops under general Oscar Potiorek bombed Belgrade on July 29, 1914. German troops under field marshal Mackensen attacked and took the city, October 6-9, 1915, in fierce fighting that destroyed much of the city. On April 6-7 1941, German Luftwaffe bombed the city, killing an estimated 17, 500 people, almost all civilians. The city was bombed again by the Allies on April 16-17 1944, killing about 1,600 people. On October 20, 1944, the city was liberated by Yugoslav partisans and the Red Army. This time city was not shelled but took by street-to-street fighting, to minimize civilian and infrastructure costs. The NATO bombing in March-June 1999 caused considerable damage to the city, especially government and administrative buildings, hospitals, Hotel Jugoslavija, Avala TV tower, Chinese embassy, Radio Television of Serbia, where 16 employees died.