When the war of manoevre bogged down into trench-bound siege warfare, old siege warfare techniques were used - and one of these was to undermine enemy strongpoints and destroy them with high explosive.

Thousands of men were employed in the secret mining war. They dug mines and counter-mines to blow enemy tunnels - a race against time before they themselves were attacked beneath the ground.

Our tunnellers portray a Rescue Section attached to a Royal Engineer Tunnelling Company.

These men were specialists using "Proto" oxygen breathing apparatus to go into the poisonous atmosphere in the mine after an explosion and attempt to rescue their unfortunate comrades.Sadly, many of those tunnellers still lie buried deep beneath the Western Front.