At least they didn’t specify marble

If you’ve ever wondered why all the underground stations of Metro look so much alike, and why you can’t just glance out the window and find where you are from the color of the posts (as in Chicago, for instance), you have the Commission of Fine Arts to thank, in part. The CFA had oversight over Harry Weese’s station designs, and reviewed them at critical points in 1967, according to Zachary M. Schrag’s excellent The Great Society Subway: A History of the Washington Metro. Certain members of the CFA, among them architecture critic Aline Saarinen, admitted that they had little experience with underground transit—she took hired cars in New York—and yet she said, “I don’t really believe if I’m on a subway I come to and say, ‘Oh, that’s the blue station; I’ve got to get off here.'” (Schrag, p. 91)

Of course, our out-of-town visitors sometimes take the Red Line/Orange Line/etc. designations too literally, and wonder why the stations aren’t the same color as the line designation, instead of their impressive and uniform concrete gray, brick red tile, and granite.