Combined, Hopper's etchings, watercolors, sketches and oils number over 1,000. I had to limit my search to oil paintings on canvas after 1922 that hang in public museums. I excluded private collections because my interest was in what the average American felt, and I wanted the painting to hang in a place where any average American could go see it. I also started from 1922 because I felt when looking through his work (and most art historians agree) that Hopper's mature style really began then, with New York Restaurant. This left me with 47 cities.
To fund the trips to see the paintings, I kept my day job as a medical editor and divided the country into regions that I could drive around when I had enough money and vacation time: New England, The Great Plains, Ohio, the Mid-Atlantic, California, Texas, Virginia, and a few stray cities on their own. I would be tracking Hopper, who often drove across the country, ogling the people and places. Many times, I felt I had entered his footsteps or paintings. I stayed in Hopperesque lonely hotel rooms. I toured garish roadside attractions. I ate in a million Nighthawks cafes.