These photos were all taken in 1973 and 1974, documenting the graffiti-marked subway system of New York City. This was years before the Vandal Squad formed, in 1980, and was tasked with defending the subway system from defacement. By the end of that decade, over 15 years after these photos were taken, they "effectively solved the problem of graffiti in the subway system." Of course, there's still tagging happening today, but for the most part the inside of train cars are only filled with Dr. Zizmor ads.