[["Schwerer Gustav (Heavy Gustav) was a German 80-centimetre (31.5 in) railway gun designed in the 19 30s as a way to breach French emplacements.  The German Army found it very difficult to use during World War 2.", 6.0], ["The world war 2 German railway gun was called the Schwerer Gustav, or, Heavy Gustav in English. It was in service 1941 to 1945. It weighed 1350 tons, fired 7 ton shells, and an effective range of 39 km. The 2nd gun was named Dora. Both were destroyed by the Germans at the wars end to avoid capture.", 5.0]]
what's the name of the world war cannon mounted on a train
history