I have 2 sets of mars maps published by the U.S. Geological Survey in 1991. One is titled "Topograhpic Maps of the Polar, Western, and Eastern Regions Of Mars." The second is "Geologic Maps of the Western Equatorial, Eastern Equatorial, and Polar Regiosn of Mars." There are 3 maps in each set. The scale is 1:15,000,000. These are large maps, in excellent condition.