The Western Union Telegraph Building was a building at Dey Street and Broadway in the Financial District of Manhattan in New York City. The Western Union Building was built with ten above-ground stories rising 230 feet (70 m). The structure was originally designed by George B. Post, with alterations by Henry Janeway Hardenbergh. It is considered one of the first skyscrapers in New York City.

Dey Street is a short street in Lower Manhattan, in New York City. It passes the west side of the World Trade Center site and the World Trade Center Transportation Hub. It runs for one block between Church Street and Broadway. It originally ran to West Street, but the western reaches were demolished to make way for the World Trade Center in the late 1960s. It now extends to Greenwich Street. 15 Dey Street is the site of the first transcontinental telephone call.