Happens from time to time, that one of the mines explodes. you know, those explosives filled caverns that engineers dug under enemy positions. Farmers hit grenades from with their plows from time to time. Or they just spontanously explode. No easy legacy living among UXO.
Not heard about any mines going off recently, I thought the last was on Messines Ridge back in the 1950s or 1960s after a lightning strike; apparently there's another still lost around there somewhere.
it's not lost, it's sitting underneath a farmhouse in Belgium.
As an aside, of all the shit jobs you could have in WW1, I'm struggling to think of one that was worse than those poor sods that had to dig mines under the German lines. There are a few documentaries about it kicking around and on one I saw, they talked about how they would have to move through the tunnels in pitch black because the Germans might have broken in and if you were moving along a tunnel with a light then you made the perfect target for an enemy sat at the end of the tunnel with a rifle. One soldier's account talked about encountering somebody in the tunnel in the pitch dark and having to feel his uniform to try and work out if he was friend of foe and whether or not to try and stick a bayonet into him.