Battle of Verdun
The Battle of Verdun was a battle of the First World War.  It started when the German Fifth Army attacked French positions, near Verdun, on February 21, 1916.  It ended on December 18 of that year but the front line had not changed very much.  Both sides lost about 337,000 soldiers each.  Never before was industrialisation so visible in war.  They also speak about the Hell of Verdun or the Blood pump.  The Battle of Verdun is considered the biggest and longest in world history.