After the fall of France in 1940, Germany was on Britain doorstep. In danger of invasion Britain started to build up defences to repel the German invaders. Focus was first given to miles of coastline that were venerable, as the Germans were only 20 miles from British soil. Along the coastline Anti-tank stop-lines were built in an attempt to prevent the German Panzers from landing on the coast. Machine gun emplacements were put up along the coastline to try and prevent and stop enemy infantry securing a beachhead that could make it safe for reinforcements to land. To help prevent this barbwire and minefields were placed in areas that were prime targets for landings.
For the inland defences each local area built pillboxes to form a hedgehog defence against the German Blitzkrieg tactic. This is due to the multi-layered defence would leave the German spearhead vulnerable form the rear. It was also a cheap form of defence, which was needed after the loss of equipment during evacuation of Dunkirk. Around the major cities anti-infantry and anti-tank stop lines were built to try and slow down any potential attackers. Miles of anti-tank ditches dug across Britain occupied this. These were often to help natural defences such as rivers and canals to try and restrict the route of attack. As the lack of trained men meant that they had to try and prevent being out-numbered and surrounded. The British even flooded farmland to try and prevent the German tanks from being able to cross it.