Duffy's Hill is a hill located on Lexington Avenue between 102nd and 103rd Streets in the East Harlem neighborhood of Manhattan, New York City. It was named for Michael James Duffy, a Tammany Hall Alderman who spent $250,000 to build 26 rowhouses on the south side of 101st Street between Lexington and Park Avenues in 1894. He continued building between Third Avenue and Lexington Avenue up to 104th Street, a section of the city sometimes known at the time as "Duffyville." At one time, Lexington Avenue buses would detour onto Park Avenue to avoid the hill