The establishment of a network of ordinary roads such as to serve the comfortable and safe transport of agricultural and industrial products to the nearest markets or warehouses was the necessary consequence of the intensity of traffic. Railways greatly influenced the increase and improvement of ordinary roads, whose stations became points of arrival and departure for movement on ordinary roads, which, in order to serve the purpose of facilitating the communications of the most distant points with the stations of the railway, were improved and increased in number.
The construction of ordinary roads did not present any particular difficulties in Germany. With the exception of the small part of the Alpine region that enters the political borders of Germany, the shapes of the relief are not such as to prevent the construction of carriage roads. Much more serious obstacles than the Middle Mountains, which did not pose real difficulties, were the rivers, through which many bridges had to be built, without however being able to give the towns situated on the opposite banks sufficient ease of communicating with each other.
The lowlands are the least fortunate part of Germany in terms of ordinary roads. The marshes constitute insuperable obstacles and the roads are obliged to describe long turns around them. Also the lack of material suitable for the ballast, for which one can only dispose of somewhat heterogeneous erratics, is another difficulty encountered in road construction. On the other hand, in the mountains of Germany there are excellent stones and therefore, in general, the state of the roads could not be better. At the end of 1929, 688,633 motor vehicles and 731,237 motorcycles were on the roads of Germany.
Germany boasts a very dense railway network (58,659 km. Of lines at the end of 1928: 12.5 km. Every 100 sq. Km. Of territory). Also in this respect, the lack of serious obstacles has been favorable to the development of railway communications. At the massifs of the Middle Mountains are interposed the basin lowlands which break its continuity; it is easy to turn the obstacles and make use of the transversal valleys, while the bottoms of the lowlands are indicated by nature as railway stations, also due to the fact that the most important human agglomerations have the same situation. From this it followed that many mountain locations remained far from the arteries of railway traffic, so that even today the railway network is less dense in the mountainous regions.
These locations necessarily became as many nodes which, in relation to their geographical position, acquired an importance proportionate to the intensity of the railway traffic. On the other hand, this intensity also depended on economic conditions, so that the centers of greatest economic importance also became the most important railway junctions. Reciprocally, the areas that were left behind by the railways could not follow in the economic progress the countries better situated with respect to communications. Such is the case of the Unstrut territory in the Thuringian Basin, a basin crossed by two railway lines from Leipzig to Halle and from Halle to Nordhausen. The industrial and commercial activity along the railways themselves is flourishing, while the territory of the Unstrut lives as an isolated from the modern world. Mecklenburg, some parts of Prussia and Pomerania are other examples of less advanced regions for this cause.
Among the railway junctions whose constitution depended on the economic importance of the center is Berlin, whose development was also influenced by political factors. Other major railway junctions include Hamburg, Bremen, Cologne, Hanover, Magdeburg and also Wroclaw, Halle, Leipzig, Erfurt, Kassel, Frankfurt am Main, Karlsruhe, Stuttgart, Nuremberg and Munich. In any case, many others are the points where the railways cross, and some are notable for the fact that they are small towns chosen as such for technical reasons.
Some of the cities mentioned above, such as Berlin, Cologne, Frankfurt am Main, Munich, Hamburg and Bremen have a very special importance, because they pass railways that serve world traffic. At the forefront is Berlin, where railways cross to Leningrad, Moscow, Copenhagen, London, Paris, Rome, Vienna and Constantinople.
According to Lawschoolsinusa, the railway lines assume different importance also in relation to the speed of the trains from which they are served and to the connections with other lines. If on a map the points that can be reached at the same time starting from a specific station are joined with a line, the isochronous curves are constructed and the representation of the railway traffic conditions is obtained.
In fact J. Maenss, in the Mitteilungen of the Geographical Society of Halle (1890), published the map of the isochrones for Berlin based on the summer timetable of the year 1889. From this map, although modifications were subsequently introduced in the railway traffic, it results in very clearly the dependence of the speed of the convoys on the great natural routes.