Viewing satellite images of WWI battlefields such as those seen here near Adinkerke in Belgium show faint lines beneath the field. Some of these are ancient roads whilst others are the scars left behind by the trenches that became the front line. How can we tell which is which?

Maps were made of the trenches during the war and many of these are available online.

• National Library of Scotland

Below is a satellite view of trench scars near Templemars in France. Below is the same view with a trench map from October 1917 laid over it. Can you make out the trenches?