The Carnegie Hill Historic District comprises East 86th Street to East 98th Street, from Fifth to Lexington Avenues. The area has a distinctive topography, situated on a hill that creates a unique sense of place. The historic district includes roughly 400 buildings. The district was designated in 1974 and expanded in 1993. The district’s primary period of development was between the late 1870s and the early 1930s. There are several significant building types within the district; rows of brick and brownstone townhouses from the 1870s through 1890s, large freestanding townhouses and mansions from the 1900s through the 1930s and flats buildings and apartment hotels from the 1900s through the 1930s and larger apartment buildings from the years following World War I to the 1930s.

The name dates from the first years of the twentieth century, after Andrew Carnegie constructed his mansion on Fifth Avenue and 91st Street. Carnegie purchased land in what was then referred to as “Prospect Hill,” a section already well-developed with row houses and a few modest apartment houses and tenements.

The decision by a man as wealthy as Carnegie to build on 91st Street had a tremendous effect on the area’s character; other mansions and a succession of luxury apartment houses soon appeared throughout the neighborhood. One can trace the waves of development by noticing the houses, which are a mix of neo-grec and romanesque revival row houses (from the 1870s and 1880s), and neoclassical and neo-federal style houses of the first decades of the twentieth century.