The Marble Twin's Story begins with the construction of the St. Regis Hotel. Furious about the 18 story hotel, the wealthy denizens of the neighborhood began rapidly buying up the surrounding real estate in order to control development. On Fifth Avenue between the Union Club and the Plant mansion, George Vanderbilt commissioned the firm Hunt & Hunt to build two matching townhouses. The houses that would become known as the marble twins were built such that they could be combined to form a larger mansion. Completed in 1905, they were in the style of Louis XV and presented Fifth Avenue with a unified facade. The Vanderbilts then sold them to wealthy friends (along with conditions that hotels or apartment buildings would never be built on the grounds.) The Goelet family moved into 547 and Willaim B. Sloane purchased the other for his daughter. Eventually, as society moved northward, the two twins were converted for commercial purposes. Gimpel & Wildenstein, fine art dealers, leased 547 Fifth Avenue and used it as a gallery to sell their collection of old masters. It would largely remain unchanged until American Express renovated it in 1938 in a commercial alteration that destroyed its graceful stone balcony and refined the first story. Seven years later, its twin 645 Fifth Avenue would be demolished. 647 Fifth Avenue would survive though and when Versace leased it in 1995 it would pay for a restoration of its original balcony and first floor. The corner twin is now the last of the many Vanderbilt built mansions that once lined this part of Fifth Avenue.