The item is a duplicate of MP/DOV0651, except that it is printed on cloth; it is a copy of MP/DOV0650. The bomb-proof tunnels are shown in red, and the splinter-proof tunnels are shown in blue. Tunnels shown in green are only 4ft high.
Copyright Crown Copyright. Historic England Archive
People & Organisations
Creator of Archive: Royal Engineers
Hanoverian Bastion, Early 20th Century Military Headquarters, Early 20th Century Tunnel