World War 1 trench over a century later
Some fact: many of the WW1 major battlefields, like the Somme or around Verdun, are still today considered as "Red-Zones" where visitors have to follow delimited paths. This is because so many shells and explosives were used, and many of them still remains underground and are very dangerous.
An incident, some 4-5 years ago, a truck driver had an engine problem and stopped on the side of a country road, the weight of the truck triggered a Moutarde-gas shell that was still there and it leaked... Two people were severely wounded by the gas, road was closed, bomb squad and hazmat teams cleared the area for weeks
