U1 (Berlin U-Bahn)

Overview
System	Berlin U-Bahn
Locale	Berlin
Stations	13
Operation
Opened	15 February 1902
Events
Wittenbergplatz–Uhlandstraße extension	12 October 1913
Separation of U1 and U2	1912–1913
Technical
Line length	9.0 km (5.6 mi)
Track gauge	1,435 mm (4 ft 8 1⁄2 in) standard gauge Kleinprofil
Electrification	Berlin S-Bahn: 750 V DC third rail
Route map 8.7 Warschauer Straße (WA) from Warschauer Straße Depot 7.9 Schlesisches Tor (S) 7.0 Görlitzer Bahnhof (Gr) 6.3 Kottbusser Tor (Kbo) 5.4 Prinzenstraße (Pr) 4.4 Hallesches Tor (Ho) 3.9 Möckernbrücke (Mo) 3.3 Gleisdreieck (Go) 2.2 Kurfürstenstraße (Kus) 1.7 Nollendorfplatz (Nu/Nm) to (ex. BI) from (ex. A) 0.9 .0 Wittenbergplatz (Wt) to (ex. AI) to (ex. AII) 0.8 Kurfürstendamm (Kfo) 1.2 Uhlandstraße (U) 1.4 Uhlandstraße Reversing Point

U1 is a line on the Berlin U-Bahn, which is 8.8 kilometres (5.5 mi) long and has 13 stations. Its traditional line designation was B^II. It runs east-west and its eastern end is immediately south of the route of the historical Schlesischen Bahn (an extension of the Berlin Stadtbahn) at the Warschauer Straße S-Bahn station and runs through Kreuzberg, Wittenbergplatz on to the Kurfürstendamm.

The eastern section of the line is the oldest part of the Berlin U-Bahn, although it is largely above ground.

The U1 route was originally part of B^II until 1957, where it was renamed to B^IV until 1 March 1966. While the main section between Wittenbergplatz and Schlesisches Tor has been designated as line 1 since 1966, the western end of the line has changed twice. It was consequently renumbered to Line "3" and "U3" in 1993, before renaming to Line U15 until 2004.

The increasing traffic problems in Berlin at the end of the 19th century led to a search for new efficient means of transport. Inspired by Werner von Siemens, numerous suggestions were made for overhead conveyors, such as a suspension railway, as was later built in Wuppertal, or a tube railway as was built in London. Finally Siemens and some prominent Berliners submitted a plan for an elevated railway on the model of New York. These people opposed Siemens' suggestion of building an overhead railway in the major street of Friedrichstrasse, but the city of Berlin opposed underground railways, since it feared damage to one of its new sewers.

Finally, after many years and negotiations, Siemens proposal for an elevated railway line from Warschauer Brücke via Hallesches Tor to Bülowstraße was approved. This was only possible, however, because it passed through poor areas. The richer residents of Leipziger Straße pressed the city administration to prevent the line using their street. Siemens & Halske carried out all construction work and also owned the line. The first sod was turned on 10 September 1896 in Gitschiner Straße. The construction work had to be carried out quickly because the contract with the city of Berlin, signed with the granting of the concession, specified that the line had to be finished within two years, or a penalty of 50,000 marks would be payable.

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Wikipedia