"Greenland" invades "Blueland" - Action lies ahead.. and a tracked gun moves up, Camouflaged, loaded with spare cans of petrol - ready to play its part in "Exercise Holdfast." In foreground Brig. R. Younger (Second from Right), of the British 7th Armoured Brigade, watches from his wayside command post. More than 150,000 troops and 800 aircraft are involved in "Operation Holdfast" Biggest allied Manoeuvres in Western Germany since the war. The exercise is to test the Allied Armies and air forces in a holding action against "Superior Enemy Forces." Eastern Forces, or "Greenland," have already invaded "Blueland". September 20, 1952. (Photo by Paul Popper).