Page:Interregional Highways.pdf/82

66 cars) with destinations at the center of the city, and those serving the organized transportation business of bus and truck lines.

The former (generally termed parking garages) constitute a more or less separate problem which is more fully discussed later in this report.

The latter are interrelated with the terminals of other transportation media, such as those of rail, water, and air.

Union bus terminals are desirable. They should be located at points convenient for express highways to provide for adequate interchange of passengers with railroads, wharves, and airports, and for collection and conveyance of passengers from and to the principal city areas in which their trip origins and destinations lie.

Truck terminals also should be conveniently accessible by the express highways, and these should be located at points appropriately chosen to facilitate the transfer of freight to and from railroad and water transportation especially. Again union terminals are desirable, not only for convenience of transfer to other modes of transportation but also for promotion of the possibilities of return truckloads.

Different classes of freight may require the establishment of more than one such terminal. The terminal for industrial freight, for example, should be located in or convenient to the area of principal industrial concentration. Another terminal may be required in or near the commercial center; and another at a point convenient for the transfer and delivery of agricultural produce. The latter would serve as both terminal and produce market and should be designed accordingly in both location and space accommodation.

In all cases, the essential service requirements of these highway terminals, both passenger and freight, will fix them within certain more or less prescribed areas, and this prescription: will have an important bearing upon the location of the interregional and other express highway routes.

Relation to other transportation media.—At cities, especially, it is important that the location of interregional routes be so chosen as to permit and encourage a desirable coordination of highway transportation with rail, water, and air transportation. Incidentally, it may be mentioned that opportunities for joint use of new structures by the interregional routes and mainline railroads should not be neglected wherever they may appear. The feasibility of combination rail-and-highway tunnels to eliminate the costs of snow removal or protection and to reduce grades over some western mountain passes, should be carefully investigated. It will be desirable to study at numerous points the possibilities of providing in a single structure, whether bridge or tunnel, for the crossing of rivers and other bodies of water by interregional routes and main railway lines.

However, it is at the cities—terminals alike for the interregional routes and all other transportation media—that the closest attention should be paid to the possibilities of common location, and also to such location of the highways as will best and most conveniently serve to promote their use in proper coordination with other transportation means.

There are possibilities of the development of common city approaches of rail and highway, either in parallel surface or depressed location, or with the highway above a railway tunnel. These possibilities should be carefully explored.