Michael Hertz, the graphic designer who helped make the New York City subway system legible for more than four million riders a day, died Feb. 18, at Nassau University Medical Center. He was 87.

In 1979, Hertz’s firm, Michael Hertz Associates, debuted a new map for the New York City subway. The map replaced Italian artist Massimo Vignelli’s abstract design from 1972, which was seen to have sacrificed accuracy for aesthetics, and prompted a flood of complaints from straphangers. Hertz and his team’s answer was to orient the map around recognizable landmarks like Central Park, and evoke the real geography and neighborhoods of the five boroughs.

While Hertz’s firm’s design has undergone revisions since 1979, including by Hertz himself in 1998, the template remains in place. “All New Yorkers carry some image of Mike’s subway map in their heads,” said Chuck Gordanier, the chief of marketing and advertising for the New York Metropolitan Transportation Authority.