Frankfurt Airport long-distance station to Kassel-Wilhelmshöhe train with Deutsche Bahn (ICE)

Deutsche Bahn (DB) is Germany’s main train operator, running around 40,000 domestic and international services each day. Its fleet includes a variety of train types: high-speed ICE (Intercity Express) trains, reaching up to 300 km/h; IC (Intercity) and EC (EuroCity) trains for long-distance travel; and IRE (Interregio-Express), RE (Regional Express), and RB (Regionalbahn) services for regional and local connections. While bathrooms are standard on all trains, amenities such as onboard restaurants and free Wi-Fi are available only on certain train types and routes. DB offers a wide range of fares, including Super Saver, Saver, and Flexible tickets, along with discount cards like the BahnCard 25, 50, and 100. Additional options include single tickets, day tickets, and group tickets. Popular routes include Berlin–Munich, Hamburg–Frankfurt, Cologne–Stuttgart, Berlin–Dresden, and Hamburg–Cologne, as well as numerous regional services across Germany.

Hessische Landesbahn (HLB) is a regional transport company owned by the German state of Hesse, headquartered in Frankfurt am Main. It provides extensive bus and rail passenger transport services within Hesse and extends its operations into neighboring states like Bavaria, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, and Thuringia. HLB operates as a holding company with subsidiaries managing rail services (HLB Hessenbahn GmbH), bus services (HLB Hessenbus GmbH), and infrastructure/vehicle resources (HLB Basis AG). Their diverse fleet includes modern train types such as Stadler FLIRT, Alstom LINT, and Coradia Continental trains. Tickets from Deutsche Bahn are also valid on HLB trains.

FlixTrain is a German railway company owned by FlixMobility, the parent company of FlixBus. Since 2018, it has connected major German cities such as Hamburg, Cologne, Stuttgart, Berlin, and Frankfurt, and also operates routes in Sweden, including Stockholm to Gothenburg. All FlixTrain services run on 100% renewable energy. Onboard facilities include air conditioning, toilets, USB ports, power outlets, generous legroom, and free Wi-Fi on most trains. Food and drinks are available, and every ticket guarantees a seat. Passengers can bring luggage free of charge, provided it fits in the racks. Popular German routes include Berlin–Hamburg, Frankfurt–Stuttgart, and Cologne–Hamburg, offering a sustainable and comfortable way to travel

Intercity is a widely recognized brand for express train services that connect cities over longer distances, often with limited stops and comfortable carriages for long-distance travel. The term "Intercity" originated in the United Kingdom in 1966 with British Rail's electrification of the West Coast Main Line, becoming a brand for their main-line passenger routes. Today, Intercity services vary across Europe, with some countries like Switzerland offering modern, high-standard trains, while in others, they may be older compared to newer high-speed options. Many European countries use "InterCity" as an official brand name for regular, long-distance train services meeting specific speed and comfort criteria. For example, PKP Intercity is a major Polish rail operator connecting cities and tourist resorts within Poland and across Europe. Trenitalia's Intercity trains in Italy offer an affordable and widespread means of rail transport, connecting various cities and towns. These trains typically offer Standard and First Class services, with amenities like power sockets and sometimes catering.