Following work recently brought into sharper focus by the Defence of Britain Project, this is the first extensive overview of the military structures of the twentieth century, combining both documentary and fieldwork research. The book presents details of all those elements of the landscape, both urban and rural, which have resulted from the need to defend against conflict - actual or threatened. Defending Britain explains both the form and purpose of structures such as anti-invasion defences, airfields, naval installations and barracks, munitions dumps and firing ranges, Cold War bunkers and radar sites, factories and stores, all of which are well illustrated. The final section provides the reader with a comprehensive gazetteer of surviving examples to visit throughout Britain.