Abstract
During the interwar period, an estimated 32–36% of Polish territory was covered by the Polish Military Geographical Institute’s (Pol. Wojskowy Instytut Geograficzny) 1:25,000 detailed map. At the same time, the MGI achieved a full coverage of the country by 1:100,000 tactical map. 50% of tactical map sheets were revised for the 1930s – many covered areas for which no detailed maps had been printed. Considering the fact that 1:100,000 tactical map was updated on the basis of revised 1:25,000 maps, another 17–21% of 1:25,000 detailed map sheets were finished or in progress by the German and Soviet invasion in 1939. The study confirmed additional 4% of 1:25,000 detailed map sheets as ‘partially compiled’ by the MGI and finished by the Germans. Another 17% of detailed map sheets are potentially to be found. Hypotheses, clues and evidence are presented in the paper.