The Butte de Vauquois is a single hill that demonstrates more clearly than any other site what underground mine warfare did to the WWI landscape. The village of Vauquois sat on the summit in 1914; today the centre of the village is a chain of immense craters where Allied and German tunnellers blew each other's positions for three years.
A network of restored tunnels can be visited by guided tour at weekends and on some weekdays. The aboveground walk is free and self-guided. About 45 minutes west of Verdun, easily combined with Montfaucon.