A sheen of nostalgic futurism envelops this historic yet illusory single family residence on Manhattan’s Upper East Side. Originally designed by American architect CPH Gilbert in 1902 for the bon vivant banker and philanthropist Jules Semon Bache, this 19th century townhouse has an archive of recalibration that’s as generous as its floorplan, spanning over 7,500 square feet across five floors. From the art collecting Bache and John D. Rockefeller in the 1940s to an in-house doctor in the 1970s, a multitude of architects have transmogrified this home’s design in order to meet the aesthetic desires of each generation of its residents. At street level, the facade advertises itself as a classic, pre-war, Park Avenue home.