Repairing of the Paris-Cherbourg railway, dozers clear rubble.

repairingoftheparischerbourgrailwaydozersclearrubble.jpg

The railway was thoroughly sabotaged by the Germans, including collapsing the Roche-qui-Pend tunnel in the Quincampoix valley. Three goods wagons of Picric Acid (TNP) explosive was used to complete the demolition of the tunnel, which was then dug out with Caterpillar D4 bulldozers and transfomed into a cutting.

This work was carried out by a company of the 347th Engineer General Service Regiment, with another three companies repairing the rails.

http://www.history.army.mil/html/reference/normandy/TS/COE/COE16.htm

http://en.wikipedia.org/wiki/Picric_acid