D-Day training sites were created in Britain in order to practise for Operation Overlord, the invasion of Northern France by allied forces in 1944.

In 1943, in an area of the Common known as the Lion's Mouth, Canadian troops constructed a replica of a section of the Atlantic Wall.

It is constructed from reinforced concrete and was used as a major training aid to develop and practise techniques to breach the defences of the French coast prior to the D-Day landings.

Over the years the wall has become colonised by alkaline-loving lichens, mosses, ferns and other plants because the concrete provides the lime-based substrate that these species require and which is found nowhere else in the locality.

[24] In July 2022, during the 2022 United Kingdom heat wave, a series of wildfires took place in the common, each of which was described by the fire services as a "major incident".

[26] To protect the structures on the common and the valued training area, the MoD provided a contracted Eurocopter AS350 for aerial firefighting operations.