Battle of Monte Cassino
The bombing in the morning of February 15, 1944 involved 142 Boeing B-17 Flying Fortresses heavy bombers followed by 47 North American B-25 Mitchell and 40 Martin B-26 Marauder medium bombers. They dropped 1,150 tons of bombs on the abbey. This turned it into rubble. II Corps artillery shelled the mountain. The German positions above and behind the monastery were untouched.