Throughout the nineteenth century, the villages of Harlem to the north and Yorkville to the south grew, while Carnegie Hill remained a collection of shanties, squatter's shacks, churches, charitable organizations, and a few town houses. It was not until the construction of the New York Elevated Railroad on Third Avenue in 1881, that the neighborhood began to change. During the 1880s, construction began on luxury brownstones on the side streets.
It was the construction of Andrew Carnegie's mansion on 90th and 91st streets that established the neighborhood as a premier residential location. In 1898, when the steel magnate purchased land outside of Millionaire's Mile, land speculators rushed to invest; however, Carnegie himself had bought up much of the land and sold it to developers only when satisfied with their plans. This included financier and philanthropist Otto Kahn, who built his mansion at the north corner of 91st and Fifth. Even after Carnegie's death, his family had an influence on development in the area. Carnegie's widow sold the plot at the southeast corner of 90th and Fifth to the Episcopal Church of the Heavenly Rest in 1925, with the stipulation that a Christian church no taller than 75 feet be built there. In 1928, Mrs. Carnegie sold 22 East 91st Street to the Spence School, a lot that also had height restrictions.
Historic architecture in the district represents two major phases of development. In the 1880s and 1890s, row houses were constructed in the neo-Grec, Romanesque and Renaissance Revival styles. When Carnegie's mansion was completed in 1902, larger residences and apartment buildings, constructed in the Federal Revival style, replaced the row house construction of earlier decades. This type of development continued until the Depression hit in 1929.
While the area remains a residential district, many buildings have been converted into shops, schools, and museums. The former Carnegie mansion now houses Cooper Hewitt, National Design Museum. The Warburg Mansion (1908), designed by architect Charles P.H. Gilbert in the French Gothic style at 1109 Fifth Avenue, is now The Jewish Museum. Other cultural institutions of note within the district include Frank Lloyd Wright's Guggenheim Museum, constructed in 1958 and considered one of his masterworks. ©2014