Paris Gun

The Paris Gun is a German long-range siege gun used to bombard Paris from a distance of roughly 120 kilometers during the First World War, first fired at the city in March 1918 as part of the German spring offensive, intended primarily to damage civilian morale rather than achieve significant military effect. Its extraordinarily long barrel, over 34 meters including a smoothbore extension, fired shells to an altitude of roughly 40 kilometers, reaching the stratosphere, the first man-made objects known to do so, and the barrel required frequent replacement due to extreme wear, with shells numbered and fired in sequence to compensate for the progressively widening bore. The gun killed roughly 250 people across the shells fired at Paris over several months, but it was withdrawn and its design details kept secret enough that no complete example survived the war for postwar examination, leaving some technical details still debated.