Philip Ashforth Coppola has spent the last 38 years illustrating the details of New York City’s subway stations. Many of the illustrations are done with ballpoint pen and are exquisitely detailed. New York Bound Books has published small editions of bound volumes of some of the sketches. This video is from the Great Big Story series.
There’s a lovely article on the NYTimes and there is also a 30 minute film short called One Track Mind that also details Coppola’s work.