the city, passing either through adjacent suburban areas or through the outer and less congested sections of the city proper.
Generally, such routes can be so located as to serve both as arteries for the conveyance of through traffic around the city between various approach highways and as distribution routes for the movement of traffic with local origins and destinations to and from the various quarters of the city. The pattern of such routes will depend upon the topography and plan of each particular city. At most relatively large cities the need will be for routes completely encircling the city.
In the larger cities more than one circumferential route may be needed. A series of them may be provided to form inner. and outer belts, some possibly within the city itself, others without. In the largest cities one such route may be required as a distributor of traffic about the business center. Often, it may be possible to serve this function by suitable locations of several of the main penetrating arteries.
Not all of these routes may be needed for the service of traffic on the interregional system, however. In some cases the needs of the interregional traffic may be largely met by a route around one side of the city, traversing only a part of the city’s circumference.
Relation to traffic-generating foci and terminals.—Railway terminals, both passenger and freight, wharves and docks and airports, generate large volumes of street and highway traffic. Much of it is of express character, and significant fractions are associated with the essential interchanges between the several modes of transportation. Both passengers and freight are transferred between railroads and ships, and passengers between railways and air lines. The future development of commercial air cargo and express freight transportation should not be underestimated in considering this shuttle movement between transportation media.
Railway terminals and docks are commonly located at mid and low city points. The principal airports probably must remain at or beyond the fringe of the city.
The location of the interregional routes at cities—both the city-penetrating main routes and the circumferential.or distribution routes—should be so placed as to give convenient express service to these various major traffic-generating foci within and in the environs of the city, and also to the business center of the city, the wholesale produce market, main industrial areas, principal residential sections new housing developments, and the city parks, stadium, baseball park, and other sports areas.
Location of the routes should be determined in relation to such foci in the positions where they are planned or are likely to be in the future and not where they are at present, if change is reasonably to be expected. Thus the closest possible cooperation is needed between highway, housing, and city planning authorities, railroad, motorbus, and truck interests, air transport and airport officials, and any other agencies, groups and interests that may be in a position to exert a determining influence upon the future pattern and development of the city.
Moreover, the highways themselves should have their own adequate terminal facilities—facilities hitherto sadly lacking. There are two general classes of highway terminals—those designed for the daily or overnight accommodation of private vehicles (principally passenger
