Michael Sorkin is a New York–based architect, urban planner, educator, and the author or editor of more than a dozen books, including Variations on a Theme Park (1991) , Exquisite Corpse (1994), and After the World Trade Center (2002). His latest book, which examines the history and changing face of New York through the lens of his morning commute, is Twenty Minutes in Manhattan.

THE IDEA FOR THE BOOK CAME ABOUT FIFTEEN YEARS AGO. Walks are contemplative times and spaces, and going over the same territory day after day gave me the opportunity to see things over the relatively longue durée : construction projects, seasonal activities, changes in commercial life, in culture, in the population. After dilating internally on the happy accidents