We're celebrating the birthday of a special New Yorker: The city's subway system turns 116 years old Tuesday. A lot has changed since 1904, the trains are faster, and horses and cyclists don’t fall into holes in the street during construction anymore. But a lot remains the same—like hot, smelly stations and people blocking doors.

John Morris is the author of a detailed new book titled: Subway: The Curiosities, Secrets, and Unofficial History of the New York City Transit System. He spoke with WNYC's David Furst about the history of the subway.