The 21 cm Mörser 16 (21 cm Mrs 16), or 21 cm Lange Mörser M 16/L14.5, was a heavy howitzer used by Germany in World War I and World War II (although classified as a mortar (Mörser) by the German military). It was based on the earlier 21 cm Mörser 10 but had a longer barrel, a gun shield and other refinements. Originally, it broke down into two loads for transport but the Germans rebuilt surviving guns during the 1930s with rubber-rimmed steel wheels to allow for motor traction in one piece with a limber under the trail and generally removed the gun shield.
