Nettleden.com - a place for explorers

The Royal Observer Corps' main task was identifing hostile aircraft until the 50's, the start of the Cold War. The increasing threat of nuclear attack promoted the House of Commons to announce that the ROC was to be chosen for the new role of reporting nuclear blasts and monitoring fall-out, this lead to the job of building 1,563 underground monitoring posts across the country.

ROC posts - More info on the ROC bunkers across the country