One of the most robust demonstrations of the long-term permanence of street systems, plot patterns and building arrangements and their impact on urban life can be found in New York. In 1811, the Manhattan plan established 12 avenues, 155 streets and approximately 1,750 street blocks. Indirectly, by determining the dimensions of each street block, the plan established the size of plots and, through their narrow frontages, defined the position of buildings. With these simple proposals, the plan successfully defined Manhattan’s ground plan while also providing flexibility for the development of its building fabric and land uses. From the early nineteenth century to the early twenty-first century, the ground plan underwent various pressures and changes, especially during the second part of this period. After examining the relationship between urban form, socioeconomic diversity and environmental sustainability, we present detailed evidence on the permanence of street systems, plot patterns and building arrangements in one of the worlds’ most vibrant cities.