Transportation planning in the United States is a complex endeavor involving federal, state and local governments. Transportation planning and road design have two main purposes, to create mobility and accessibility. Different designs are used for different functions. For instance an interstate a few access points but high speeds for mobility. Conversely, cul-de-sacs have high accessibility with limited mobility.
The urban fabric comprises of a complex network of phenomena. Spanning time and consisting of many layers; community design, the marrying of architecture, planning and socioeconomics - planning is a response to current phenomena. Thought of as a positive response to the ills of that era.
For example, the Garden City inspired Radburn plan in Fairlawn, New Jersey, some 16 miles from New York City, and designed by Clarence Stein and Henry Wright. The Radburn plan was a direct response to increased automobile usage, congestion, squalor, and gridiron of New York City at that time in the mid 1920s. The Garden City concept implemented curvilinear streets, used a hierarchy of streets, and conserved land for public green space.
