Royal Observer Corps Headquarters, York

The Royal Observer Corps Headquarters at York was one of 31 built in the United Kingdom in the early 1960s. It’s a semi-sunken bunker, others were entirely on the surface, while some reused earlier structures.

The Royal Observer Corps had its origins in the First World War as part of the country’s air defences when its role was the visual reporting of airship and aircraft movements. This function continued in the Second World War and into the Cold War, and in the 1950s inspired a similar system in the Netherlands. In the late 1950s, in the event of a nuclear attack the Royal Observer Corps acquired a new task of reporting the locations of nuclear detonations and the spread of resulting fallout.

At its height the system comprised around 1500 small monitoring posts reporting to 31 group headquarters.

Nuclear fallout knows no boundaries and systems were in place to exchange information with analogous organisations in France, Belgium, Denmark and the Netherlands.