The Vienna U-Bahn is the rapid transit system serving the city of Vienna, Austria. It consists of five lines, designated U1 to U6, covering a total of about 83 kilometers. The U-Bahn is known for its efficiency, cleanliness, and punctuality, making it a popular choice for both locals and tourists. Opened in 1978, the U-Bahn connects key areas of the city, including historical sites, shopping districts, and residential neighborhoods. Trains run frequently, and stations are equipped with modern amenities. The system is an integral part of Vienna's public transportation network, which also includes trams and buses.