Lately, Russia seems to be soft-pedaling their attempts at world domination, choosing to use ads on Facebook or Youtube clickbait to exert their influence over global politics rather than overt threats of nuclear annihilation. But, of course, this wasn’t always the case. As well as providing a fascinating look at perhaps one of the most comprehensive pre-Google Maps mapping endeavors ever, John Davies and Alexander J. Kent’s The Red Atlas: How the Soviet Union Secretly Mapped the World is a surefire way to reignite those bygone feelings of Cold War paranoia by demonstrating just how serious the Soviets may have been about invading a town near you, or your actual town, as the case might have been for many of America’s larger metropolises. Including, as the maps below illustrate, Chicago.

As a review of the book in a recent issue of National Geographic notes, the detailed Russian maps–some of which were only smuggled out of the country within the last decade–were compiled from a variety of sources, including information borrowed from contemporary USGS maps, which the Soviet maps seem to mimic extensively. But other specifics, like detailed depictions of depths and channels around rivers and harbors, including the Soviet-era map of Navy Pier shown below the USGS version of the same area, are notably different from the USGS figures, and could only have been gained by actual Soviet feet on the ground.

What the precise motive was for the attention paid to these details ,and the painstaking lengths Soviet intelligence must have gone to obtain them are matters of speculation, but according to Davies and Kent the Soviet-era maps they have uncovered for their book would have supported a full range of military planning.

For more read the article on the National Geographic website or if you’re in the UK check out this piece on the secret soviet maps of London that mapped out the entire city in excruciating detail, neighborhood by neighborhood.