Map Showing the Height and Area Districts of the Borough of Manhattan

This fascinating map of Manhattan outlines the various districts created by influential zoning legislation introduced in the early 20th century. On the base map, Residence, Business, and Unrestricted districts are shown according to the legend in the lower right. Height districts, numbered and outlined in overprinted green, dictate the maximum degree of building profile (the higher the number, the taller the possible structure). Area districts (overprinted red) represent the available lot percentages for building construction.

New York City’s 1916 Zoning Ordinance was a groundbreaking law that established the first comprehensive zoning code in the United States. Sections were dedicated to controlling building height and land use in order to prevent the city from becoming overcrowded, miasmatic, and dark (a serious problem in the rapidly growing metropolis). The law’s most well-known feature was the “setback” rule, which required skyscrapers to narrow in width as they rose in height, ensuring sunlight and fresh air could reach the streets below.

Through the 1920s, the ordinance was largely maintained, but developers found creative ways to maximize building size, leading to the creation of iconic, Art-Deco style skyscrapers that defined the decade’s architecture.

The map was created by the Ohman Map Company, Inc. of Broadview, New York. Originally published in the 1928 edition of the Diary and Manual of the Real Estate Board of New York.