1941 WWII London Underground map in color, 20.5x24, with advertisement on verso. Designed by H.C. Beck after his return to the position as lead map designer. Beck's underground maps had been published since 1933. Beck's maps are entirely schematic and largely non geographical design for the railway system, considered to be a landmark of twentieth century information design. In 1938 Beck's design was altered by Hans Schleger, and this new design was published in 1938, 1939 and 1941. The map maintained all the elements of the Beck's circuit approach but with distinctive modification with blue-green background intended to highlight the central area. It shows early signs of zoning, and does not include the iconic Underground logo on the map. On his return in 1941, Beck was asked to use interlinking circles for the interchange stations. This map shows advertisements at the top and bottom of the map.