This book was originally conceived to provide a comprehensive survey of
the numerous underground nuclear Monitoring Posts in and around South
Yorkshire during the period known as the "Cold War" (1946 to 1991).
These sites were operated by the voluntary body of men and women of the
Royal Observer Corps; whose origins date prior to World War 2 (WW2), and
who occupied these Posts to provide a secretive warning and monitoring
role in the event of a nuclear attack on the United Kingdom during the
"Cold War". As the initial research to this book progressed; other
protected sites were identified and were considered to be just as
significant to the "Cold War" period and ultimately required inclusion.