As already mentioned, the nature of the country opposes very serious obstacles to the creation of an organic network of rapid communications, fully responding to the modern needs of the transport of goods and travelers both within the borders of the kingdom and between the kingdom and the states neighboring. To the elongated configuration in the sense of latitude, where greater distances exist between the extreme northern and southern points than in other much more extended states, the presence of the Apennine mountain system, which hinders direct communications between the two main seas, is added to the geological structure. unfavorable to many areas, where the presence of clayey rocks, unstable and falling apart, makes the construction of ordinary and railways difficult and expensive, the irregular nature of many watercourses, whose wide valleys subject to floods must have been rather escaped than sought by the communication routes, finally the presence, especially in the past, of marshy areas along the coasts, also avoided due to the raging of malaria. To these natural difficulties was then added in the past also the political division and the divergence of economic interests between the ancient states.
The first Italian railway section, from Naples to Portici, was opened on 4 October 1839; before 1850 there were no more than 600 km in Italy. of railways. The total length had risen to 6200 km. in 1870, at the time of unification, but it had to do, at least in part, with lines created to serve the individual states and not in the interest of traffic through the new unitary state. From 1870 onwards, great progress was made, thanks to the direct intervention of the government, and, although the implementation of the railway program suffered stops and slowdowns, the aforementioned natural obstacles were gradually overcome with the use of sometimes grandiose technical means ( construction of long tunnels), and subsequently the major obstacle that stood in the way of the railway connection with the finite states was also overcome, the Alpine chain, now crossed by seven major lines and some other minor ones. The current Italian railway network, even if it lags behind that of the other major European states more favored by natural conditions due to the density of the mesh, is gradually taking on the character of an organic system, adapted but necessarily to the geographical conditions, but always better responding to the needs of industries and intensified internal and foreign relations.
The network, reported at about 20,000 km. before the World War, it rose (1 January 1932) to 22,522 km., and to 26,557 if the secondary railways and suburban tramways are included. They are standard gauge about 21,700 km. and of these about 3000 km. electric traction. The state includes 16,850 km., Of which over 4000 double-track and 1940 electric-powered. This traction system has been significantly developed in recent years, even in lines of primary importance (such as the Modane-Turin-Genoa-Livorno, the longest electric traction line currently in operation in Italy); at the end of 1931 there were more than 3400 km in Italy. of electrified lines (including secondary ones). The complete work plan for the next 10 years includes the electrification of the main arteries of the state railway system for a complex of over 4000 km. of lines.
On average there are just over 8 km in Italy. of railways per 100 sq. km., while in Great Britain there are 13, in Germany 12, in France 10 (in Belgium 37). In relation to the population there are just over 5 km. for every 10,000 inhabitants (France 13, Germany 9, Great Britain 8, Belgium and Switzerland 14). No Italian municipal center is more than 50 km away. from a train station. The densest network is found in the Po-Venetian Plain, both because there are no major natural obstacles, and above all because here is the seat of the most flourishing and developed industries. There are two major arteries in this region, one current at the foot of the Alps (Turin-MilanVerona-Venice – Udine-Trieste) and one at the foot of the Apennines (Alessandria-Piacenza-Bologna-Rimini); they are united by numerous transversal (main: Turin -Alessandria; Milan-Bologna; Verona-Bologna; Venice-Ferrara-Bologna, etc.). Major railway nodes are Milan, Turin, Verona, Bologna and Venice-Mestre. The aforementioned lines are connected on one side by those that cross the Alps, leading to France (Turin-Nice and Turin-Modane; also the Genoa-Nice-Marseille coastal road), to Switzerland (Milan-Domodossola-Briga and Milan-Chiasso-Lucerna ), in Austria (Verona-Bolzano-Innsbruck and Bolzano-Lienz; Venice-Udine-Villach), in Yugoslavia (Trieste – Postumia – Ljubljana; and Rijeka – Zagreb), on the other the lines for peninsular Italy. In this, two longitudinal lines of heavy traffic run along the coast or a short distance from it, one from Genoa (or rather from the French border in Ventimiglia) to Livorno, Rome and Naples, up to Reggio Calabria, the other from Rimini, for Ancona, Foggia and Bari to Brindisi, and from Bari, for Taranto, in Reggio Calabria. The most important internal longitudinal line is that from Bologna, to Florence, to Rome and to Naples; it crosses the Tuscan Apennines at a considerable height (616 m.). The Apennines are then crossed by about ten transversal lines (see Apennines). The railways headed by Reggio Calabria are connected through ferry – boats to the Sicilian network, which has Messina-Palermo and Messina-Catania-Syracuse as its main arteries. Communications between the peninsula and Sardinia are carried out mainly from Civitavecchia (and also from Livorno and Genoa) to Terranova, connected by rail to both Cagliari and Sassari.
In southern Italy and the islands, where, due to the mediocre development of industries, traffic is still modest, the connection of many smaller centers to the main railways is made by narrow-gauge secondary lines, many of which are notable for their daring with which they overcome the steep differences in height by means of huge works of art or with applications of exceptional traction systems (rack). On the other hand, in the regions where the movement is greater, there is a tendency to shorten the routes, both with the introduction of rapid trains, and with the creation of very direct lines, such as the Rome-Naples (for Formia) and the one, soon to open, from Florence to Bologna which crosses the Apennines in a new tunnel about km long. 18.5, the longest in entirely Italian territory and the second in the world for length, after the Simplon tunnel.
It should be noted that the transversal lines of the Po-Venetian Plain are now also used for transit traffic between western and eastern Europe (or between the north-west and south-east ones): in fact it passes on the Domodossola- Milan-Mestre-Trieste one of the greatest European railway communications, the Simplon-Orient Express, which is joined by other international lines from Nice and Modane. On the other hand, the Modane-Bologna-Ancona-Brindisi line, previously used by the suitcase of the Indies , has diminished in importance today, as an international communication artery for the Levant, Egypt and Asia .
Overall, in the last few years (1925-29) about 108-115 million travelers and 55-65 million tons of goods per year (excluding livestock) circulated on the state railways; to these are added 60-70 million travelers and 9-10 million tons of goods transported on private railways (excluding tramways). Since 1930, the general economic depression has naturally produced a strong restriction of traffic: between 1929 and 1931 the number of travelers decreased by 24% and the weight of goods transported by state railways by 27%.