From 1940, Headley Court was used as the Headquarters for the VII Corps and later for the Canadian Corps and Canadian troops were billeted at High Ashurst. Bellasis House was used as training centre both for Czech agents of the Special Operations Executive and for German Prisoners of War. In preparation for D-Day, Headley Heath was used for tank and combat training by the Canadian armed forces, and the area known as The Pyramids is named after the piles of ammunition that they kept on the heath. Betchworth Quarry was used by the British Army in early 1944, to test the firing capabilities of Churchill tanks.