Main Building is on the Vassar College campus in Poughkeepsie, New York. It was built by James Renwick, Jr. in the Second Empire style in 1861, the second building in the history of what was one of America's first women's colleges. It is one of the earliest, largest, and most important examples examples of Second Empire architecture in the United States and is a National Historic Landmark. At the time of its completion, the structure contained the most interior space of any building in the United States, and housed the entire college, including dormitories, libraries, classrooms, and dining halls. Currently, the first and second floors house campus administration while the remaining three (including the second floor wings) house student rooms.