D-Zug

A Schnellzug is an express train in German-speaking countries, where it refers to trains that do not stop at all stations along a line. The term is used both generically and also as a specific train type. In Germany and Austria it is also referred to colloquially as a D-Zug, a short form of Durchgangszug ("through train"), and express train services were often given numbers preceded by the letter D.

On the railway networks operated by the Deutsche Bahn (DB), the Austrian Federal Railway (ÖBB) and the Swiss Federal Railways (SBB) today, express trains are divided into categories such as Eurocity, Intercity, Interregio etc. The DB still occasionally runs D-Zug services in night trains (D-Nacht), especially those to its eastern European neighbours, and as relief trains. Museum services running on DB routes are also given D-Zug numbers.

The first German express train ran on 1 May 1851 between Berlin and Deutz am Rhein (today part of Cologne) and completed the journey in 16 hours. Three months later, on 1 August 1851, the first night train ran from Berlin to Bromberg. The Prussian state demanded a country-wide network of night trains; consequently the various railway companies started up fast courier trains in the years that followed (1852 to 1854), from Berlin to Breslau, Frankfurt am Main, Hamburg and Cologne. Passengers on the night-time courier trains between Berlin and Frankfurt had to pay a higher fare for the first time in order to compensate for the higher crew costs of night-time through trains.

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