20. Carnegie Mansion, 2 E 91st St.

Cooper Hewitt, one of NYC's Gilded Age Mansions that is now a museum

The Fifth Avenue home of steel magnate Andrew Carnegie was one of the later Gilded Age mansions to be built in New York City, completed in 1902. The grand home on East 91st Street was purposely placed further north on Fifth Avenue, away from the concentration of Gilded Age elite on “Millionaires Row.” The Carnegie Mansion was designed by Babb, Cook & Willard in an English Georgian style. Carnegie spent much of his later life here, working from an office where he managed his many philanthropic endeavors. The mansion is now home to the Cooper-Hewitt, Smithsonian Design Museum.

Gilded Age Fifth Avenue Tour

The Frick, one of the many Gilded Age Mansions of NYC that has turned into a museum

Next, read about the Top 10 Secrets of Grand Central Terminal