U-Bahn is the
German abbreviation for Untergrundbahn ("underground railway"), referring to a means of urban
rapid transit, such as the "
London underground" or "
Paris métro". The term was created at the beginning of the 20th century in
Berlin, where the
Deutsche Reichsbahn Gesellschaft ("German state railway company") (predecessor of today's
Deutsche Bahn) created a system of urban and suburban railway lines with fast electric trains with short stopping intervals, called the
S-Bahn (Schnellbahn, "rapid railway"). The Hochbahngesellschaft ("elevated railway company"), operating elevated and suburban lines, decided they required an equally short and memorable name for their system, and thus called it U-Bahn, for Untergrundbahn ("underground railway"). In Germany the most common symbol for the U-Bahn is a white "
U" on a square blue background, in Austria it is on a circular background.
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