Apparently some trenches and bunkers are up for sale in the Channel Islands
http://digitaleditions.telegraph.co.uk/data/1166/reader/reader.html?social#!preferred/0/package/1166/pub/1166/page/22/article/NaN
There isn't time to dig trenches. We'll have to buy them ready-made. Here, run out and get some trenches. Wait a minute, get 'em this high...[gestures to his chin]
and our soldiers won't need any pants. Wait a minute, get 'em this high...[gestures over his head] and we won't need any soldiers!
(https://upload.wikimedia.org/wikipedia/en/7/79/Duck_Soup_Groucho_and_generals.jpg)