This Pillbox (Type FW3/24) formed part of the GHQ Line, and more specifically as part of the Green Stop Line along the Stroudwater Canal. They were located as such to protect the north and south approaches of the canal as well as the main bridges which crossed over the canal at Fromebridge, Pike Lock and at Stonehouse.
The GHQ Line (General Headquarters Line) was a defence line built in the United Kingdom during World War II to contain an expected German invasion.
The British Army had abandoned most of its equipment in France after the Dunkirk evacuation. It was therefore decided to build a static system of defensive lines around Britain, all designed to compartmentalise the country and delay the Germans long enough for more mobile forces to counter-attack. Over 50 defensive lines were constructed around Britain, the GHQ Line being the longest and most important, designed to protect London and the industrial heart of Britain.
“Stops” were to be of two types:
1. Waterways and other natural obstacles such as steep hills. As waterways provided an effective obstacle it was intended to hold these lightly in order to concentrate forces for the remainder, weaker stops. Waterways were to be made into Demolition Belts by preparing bridges and crossings for demolition. Waterways at right angle to the main line of enemy advance were of the greatest value as they would hinder lateral movement of the attack and were to always be included in Demolition Schemes.
2. Where no waterways existed the “stop” was to be organized in great depth. It was to consist of an artificial obstacle (ditch or minefield) covered by pillboxes and the bulk of the remaining anti-tank guns.