In June 1917, before the first A7Vs were even completed, the German War Ministry ordered the construction of a new colossal super-tank, the biggest tank ever designed: the K-Wagen! (K standing for Kolossal, meaning...colossal.) The K-Wagen was thought as a enormous moving fortress bristling with guns and MG:s, to be used in breakthrough situations. The weight was some 150 tons, and it would be powered only by two small 200 HP motors! (Later on these two tiny motors were switched for two 650 HP motors.) The enormous weight of the vehicle of course made it impossible to move any longer distances, so it was to be transported by rail in four parts of some 30 tons each, only to be put together behind the front line, at the point were it was to be employed. The K-Wagen was also supposed to have a trench crossing capacity of some 4 meters, and no less than four 77mm cannons. The design was done by Vollmer.

Almost from the very beginning of the project sceptical voices was heard. The sheer size of the vehicle made it difficult to produce, as no standard components or techniques could be employed. So it was decided that the tank was to be built by companies with experience from building bridges(!) and the tracks came from power shovel construction. Soon it was also discovered that the tank was too heavy, so the length was reduced to 13 meters, which at least cut the weight with some 30 tons. The original order was for ten vehicles. The weight was some 120 tons! It has been called "completely nonsensical", but two prototypes were actually under construction when the war ended - one was nearly finished. People doubting the whole idea were silenced by being told that von Hindenburg himself wished it to be built.

Weight	120 tons
Max. Armour	30mm
Max. Road Speed	7.5 km/hr
Armament	4 x 77mm 6 x 7.92mm MG 08/15
Crew	18 - 22