General Falkenhayn decided that at Verdun he would wage a battle of attrition against the French Army that would bleed it dry and drive France from the war. The longest battle of the Great War, The Battle of Verdun raged for 10 months, from February to December, 1916, and cost nearly a million casualties on both sides (but no one will ever know for sure the exact total).
The old fortress city of Verdun was ringed by strongholds and forts, the largest and most important of these being Fort Douaumont called by one writer "the most shelled spot on earth." The Germans captured Fort Douaumont in February, 1916; the French finally retook it in October. It is said that retaking Fort Douaumont alone cost the lives of 100,000 Frenchmen.
These photographs from The Illustrated London News of June 24, 1916, show the French counter-attacks on Fort Douaumont on May 22-23, 1916 (click each photo to read the accompanying text):
A still frame from Abel Gance's film J'accuse (1919). In this scene, dead soldiers on the battlefield come to life, and grope their way back to "civilization" to ask the living if the war dead, if their lives, have been sacrificed for some worthy purpose. J'accuse, and this scene especially, overpowered audiences: women fainted, D. W. Griffith and Lillian Gish were left speechless for hours. In what sounds like a contemporary review of Saving Private Ryan, a reviewer in Prague was sure that if the film "had been shown in every country and in every town in the world in 1913, then perhaps there would have been no war."
"The poignancy [of the dead men walking scene] is strengthened by what is known of the making of the film. The army provided two thousand soldiers for the sequence, most being on eight days leave after four years of fighting. Gance said: These men had come straight from the Front from Verdun. . . . They played the dead knowing that in all probability they'd be dead themselves before long. Within a few weeks of their return, eighty per cent had been killed.'" (Kelly, 103, 105).
After the war, the French closed some 16 million acres northeast of Verdun due to unexploded ordnance and uninterred human remains. Much of this area is "off limits" to this day, as it is estimated that 12 million unexploded shells still lie in the soil around Verdun.
While digging a rail line through the Somme battlefields in 1991-92, to connect with the "Chunnel," the French démineurs ("de-miners") handled an average of five tons of unexploded ordnance per day that had been unearthed during the excavation (throughout France, the démineurs collect some 900 tons of ordnance per year, with 30 tons of that being gas shells). Luckily, no one was killed during the "Chunneling" although several pieces of construction equipment were totaled but every year several French démineurs are killed and injured disposing of gas and high-explosive shells, and in 1991 alone, 36 French farmers were killed plowing up unexploded ordnance from the Great War.
And in Belgium (especially around the Ypres/Passchendaele area), according to a 1995 newspaper article, it should take yet another 15 years to destroy the stockpiles just of gas shells so far discovered. (For a glimpse at the kind of munitions stockpiles amassed for these battles, click here.)