​​On 23 March 1942, Adolf Hitler issued Fuhrer Directive No. 40 which was the order for the creation of an Atlantic Wall. 6,200km of coastline needed to be defended. They used slave labour, such as Organisation Todt, and conscripted workers to build hundreds of defensive positions. 

​WN42 is located to the east of the town of Arromanches-les-Bains on top of the cliffs. Here, the position was manned by Wehrmacht (army), Kreigsmarine (navy) and the Luftwaffe (air force). The Kreigsmarine numbered around 30 and from the elevated position were able to observe any Allied landings coming towards the coastline. The Luffwaffe at WN42 operated a Wurzburg radar with a range of 23km to detect any Allied aircraft. They also operated the three anti-aircraft guns (2cm Oerlikons) that were positioned here to target aircraft. The Wehrmacht, I. Grenadier Regiment 916, 352 Infantry Division operated the other positions of WN42. These consisted of two 75mm cannons, two 50mm mortar guns and two machine gun positions.  

​All these positions were located on the flat plateau at the top of the cliff. Many were constructed using concrete and are still visible today. This included billets for soldiers to rest and sleep in, which allowed them to remain within WN42 and be called to action immediately if required. 

​At the beginning of 1944, the large concrete casement of WN42 was completed and it was finished. It had a 75mm cannon placed inside the position. This casement can be found on the path leading down to Arromanches-les-Bains town. A Sherman tank is now located on top of the casemate. This also is recorded on some records as WN43 as well as WN42.​