It’s easy to overlook the many small bunker sites in this area as they stand on the hillside surrounding one of the Second World War’s largest and most advanced weapon sites.
Miles of deep tunnels and shafts were cut into the chalk landscape here as German forces created an underground fortress designed to unleash hell on London.
Alongside the V1 flying bomb and V2 missile, German scientists developed a long-range multi-charge cannon known as ‘Hochdruckpurge’ or V3.
The V3 was a cannon with a 127m long barrel and required the construction of gigantic underground structures, with the Mimoyecques site selected for the first of these due to distance from London.
The untested range of the weapon was around 150km – and the location was out of range of attacks from Navy guns or Commando raids.
The multi-charge gun – also known as the ‘London Gun’ due to its main target - was created in 1942 by engineer August Coenders, an expert in special shells, who hoped to exceed the range of traditional guns by increasing the initial velocity of the proposed 15cm calibre, 230cm long projectile inside the barrel.
His ‘arrow-shell’ with fins would be propelled via a series of charges along the barrel’s length - the projectile would have its trajectory accelerated by a successive detonation of additional cartridges inside chambers fitted in symmetrical pairs (there would be 32 in the final version) at each section of the gun.
The aim was to achieve an average firing rate of 2.5 rounds per hour from each barrel – 50 barrels were planned - capable of striking the target with 3,000 rounds a day, meaning 90 tons of explosive would hit the streets of London each day.
The existence of abnormal activity in the ‘Marquise-Mimoyecques’ area was noticed on photographs taken on September 18, 1943. Here, digging to create access for two parallel railway tunnels could be distinguished. The first two bombing raids were carried out on the suspect site on November 5 and 8, 1943.
While the destruction was very limited and did not affect the underground work, the site was still not ready for firing by the time Canadian forces captured the site in September 1944.
Wn521 Brenner stands to the west of the V3 launch site, in an agricultural field next to the Calais Canadian Cemetery. It’s a simple build which today offers a view from the hillside along the main A16 motorway between Calais and Boulogne.
The nearby Cemetery is the final resting place of over 700 soldiers, many falling during the liberation of the area by Canadian forces in September 1944.