Just noticed this on the BBC website and thought I'd share it.
http://www.bbc.co.uk/news/uk-19839827
http://www.bbc.co.uk/news/uk-19839827
A team of British and French archaeologists have entered a labyrinth of tunnels beneath the Somme Battlefield in France.
The tunnels, 80 feet down, were dug so that troops could lay explosives below enemy lines.