Hauptbahn

Hauptbahn, literally "main railway line," is a term used in German-speaking railway planning to designate the principal routes that form the backbone of a national or regional rail network. It distinguishes these lines from secondary or feeder routes, commonly referred to as Nebenbahnen or Nebenstrecken. In practice, Hauptbahnen are the corridors that carry the highest traffic density and accommodate long-distance passenger services, high-frequency regional services, and freight.

Historically, Hauptbahnen were the first lines built or upgraded in many countries, linking major cities and industrial centers. They were designed for higher speeds, greater train lengths, and higher axle loads, and were progressively electrified and fitted with advanced signaling. Over time they often become the core of national rail operations, subject to priority maintenance and modernization.

In modern planning, the term Hauptbahn is a functional descriptor rather than a strict legal category. Network planners classify routes by their role in services and capacity. Hauptbahnen typically support higher-speed operations and serve as main corridors for intercity and long-distance traffic, while Nebenbahnen connect smaller towns and feed traffic to the major lines. The distinction helps allocate investment, timetabling, and infrastructure upgrades, including signaling upgrades, electrification, and track upgrades.

Across German-speaking regions, numerous main lines form international and national corridors, with Austria and Switzerland maintaining parallel concepts in their rail networks. Overall, the Hauptbahn represents the essential spine of rail transport, enabling efficient movement of people and goods across regions.