The NYC architectural firm of Delano & Aldrich designed some of the turn-of-the-century’s most sophisticated structures, from the Knickerbocker and Colony Clubs to the Rockefeller’s upstate estate Kykuit to a slew of uptown mansions. At the time, they veered away from the popular Beaux-Arts style and popularized an Anglo-American mix of Neo-Classical and -Federal designs. One such example is this grand townhouse at 15 East 88th Street, just listed for $28.8 million. As the listing states, it’s one of their few intact mansions remaining in private hands. And since it’s had only a few owners over the years, it retains its historic details and stately facades.