The hypothesis of seeking to understand the city by examining the criteria of hierarchy and regularity of its urban infrastructures and transformations may help us to a different understanding of the decisions leading to the construction of the present-day city. Manhattan’s development is based on the Commissioners’ Plan of 1811, the second centenary of which was marked by a research project. The precision of layout, the judicious definition of avenues and streets, and the geometry of the city blocks are still interesting and thought-provoking@en