The Role of Pillboxes along The Kennet & Avon Canal during WW2

Military history buff John Leete explains the role of pillboxes during WW2.

‘Britain on the brink’ was how one commentator described the plight of the nation during the ‘Dunkirk’ summer of 1940 after the defeat of the British Expeditionary Force. The legacy of our readiness for determined resistance of the homeland, can still be seen today along the Kennet and Avon Canal. 

By May 1940 Germany had invaded France during a campaign that had lasted just six weeks. By the end of June the British Army had abandoned much of its equipment in Dunkirk after it beat a hasty retreat from the advancing enemy.

The Germans had two options available to them; to lay siege to Britain and wear the country down through political and psychological warfare and limited military action, or to mount a full-scale invasion.

In July 1940, Adolph Hitler issued a Directive (known as Number 16) which read ‘As England, in spite of the hopelessness of her military position, has so far shown herself unwilling to come to any compromise, I have decided to begin to prepare for and if necessary to carry out, an invasion of England and if necessary the island will be occupied’.

This was to be known as Operation Sea Lion with an invasion force ready to sail by 15 August 1940.

General Sir Edmund Ironside was Commander in Chief of Britain’s Home Forces and responsible for organising the country’s defence. He had been appointed to this role by Winston Churchill in May 1940. Whilst he had a large force at his disposal, it was inadequately armed and equipped and the men were poorly trained. His plan therefore was to set up a static system of defences to delay an invasion force and to buy time for the mobilisation of his reserves. Ironside reasoned that if the Germans could be held up on the beaches and then further delayed as they tried to push inland, their invasion timetable could be seriously compromised and their impetus lost to the extent that the British Army could then mount a successful counter attack.

The coast along the southeast of England was quite well defended with a variety of anti-aircraft guns and troops. To this, a secondary line of defence was to be added through the use of barriers or stop lines which utilised natural and man-made features such as railway lines and canals. Mile upon mile of anti-tank ditches were dug and concrete pillboxes and gun emplacements erected on key sites to take advantage of high ground or areas where the widest range of fire could be bought upon an advancing enemy. Known variously as Stop Lines or GHQ (General Headquarters) Stop Lines or Anti-Tank Lines, the purpose of these defensive positions was simple: ‘to ensnare and delay the Germans’ and to stop them ‘breaking loose’ as they had done during the invasion of France.

At the end of June 1940, the anti-invasion plan itself was complete and as Home Forces Operations Instruction no. 3 it was presented to the War Cabinet. More than fifty defensive lines had been constructed across England although some remained part completed but fit for purpose at the time. The main stop line was certainly the longest and most important for it was created to protect London and the industrial heart of England. It ran from the Taunton stop line in Somerset and followed the River Brue and the Kennet and Avon Canal to Reading, via London, Guildford and Aldershot to Canvey Island and Essex before running north to Yorkshire and Scotland. It was split into sections, one of which was known as Stop Line Blue. This ran east from Semington near Trowbridge and followed the length of the Kennet and Avon Canal to Theale.

Pillboxes and anti-tank gun emplacements, mostly constructed by local builders to a standard Ministry of Works design were sited along the length of the canal. Some were roughly disguised as sheds and others were situated under trees. Obstacles of various types, including ‘dragons teeth’ were placed on embankments and on canal bridges and much of the material used was carried on the canal.

The most common type of pillbox of the designs and variations built was the small hexagonal type, such as the ones at Sulham Gap, north of Theale, and by the canal near Newbury. These were intended for use by lightly armed troops. Larger hexagonal pillboxes were used by Bren-gun crews whilst crews equipped with two-pound field gun were housed in even larger constructions with apertures for both the field gun and the Bren. An excellent example of this type can be seen at Dun Mill Lock on Hungerford Common.

In contrast, some twenty or so miles east of Hungerford by waterway is Burghfield where can be seen an excellent example of a fortified building which stands only yards from the Kennet and Avon canal bridge on the Burgfield Road from Reading. The converted stable block would have provided an excellent all-round defence, covering the roads on both sides of the building and affording protection to the approach to the canal bridge. Some of the original embrasures (openings for weapons) can still be seen yet this ordinary building is a good example of how firepower and manpower could be discretely positioned at key points in readiness to surprise and rout an invading force.

Manned by members of the Home Guard (known as the LDV until July 1940) these pillboxes and assorted fortified positions were thankfully never used in combat for after the decisive outcome during the Battle of Britain. Hitler changed his plans and Operation Sea Lion was postponed indefinitely. Nationally, six thousand pillboxes survive of which approximately 150 can be found in Berkshire, many along the length of the Kennet and Avon Canal.

The Kennet and Avon, like so many canals originally one of the nation’s industrial arteries, fell into disrepair, was revived, became a vital part of the nation’s defence and today is part of the nation’s heritage to be enjoyed not just for its beauty but also for the service it gave in time of war.

Whilst the etmology of ‘pillbox’ has been disputed, a level of consensus has been reached which supposes that the aesthetic of the defensive structure closely resembles that of the ‘pillar boxes’. These pillar boxes – pillars with integrated letter boxes – share the appearance of the firing loopholes and slots that appear in pillboxes. 

John Leete

See also…

The History of the Swing Riots in Berkshire

Willie Willie Harry Stee – the updated mnemonic

Remembering Wartime Membury

The Night-Fright C-47 Restoration Project


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