Commissioners' Plan of 1811

The Commissioners' Plan of 1811 was the original design for the streets of Manhattan above Houston Street and below 155th Street, which put in place the rectangular grid plan of streets and lots that has defined Manhattan on its march uptown until the current day. It has been called "the single most important document in New York City's development," and the plan has been described as encompassing the "republican predilection for control and balance ...

Source: Wikipedia — Commissioners' Plan of 1811 (CC BY-SA 4.0)