71st (South African) Siege Battery, Royal Garrison Artillery was a unit of the South African Heavy Artillery formed for service with the South African Overseas Expeditionary Force in World War I. It travelled to Europe and fought under British command on the Western Front from 1916 to 1918, seeing action at Mount Sorrel, the Somme, Bullecourt, Ypres and Cambrai, against the German Spring Offensive and in the final Allied Hundred Days Offensive.