U4 (Berlin U-Bahn)

Rathaus Schöneberg, one of the five stations on the U4
Overview
LocaleBerlin
Termini
Stations5
Service
TypeRapid transit
SystemBerlin U-Bahn
Operator(s)Berliner Verkehrsbetriebe
Depot(s)Grunewald
Rolling stockA3
History
Opened1 December 1910 (1910-12-01)
Separated
from Line B
28 February 1966 (1966-02-28)
Technical
Line length2.9 km (1.8 mi)
Track gauge1,435 mm (4 ft 8+12 in) standard gauge
Loading gaugeKleinprofil
Electrification750 V DC third rail (top running)
Route map

-0.8
Reversing point
-0.1
Nollendorfplatz
0.7
Viktoria-Luise-Platz
1.6
Bayerischer Platz
2.3
Rathaus Schöneberg
2.7
Innsbrucker Platz

The U4 is a line of the Berlin U-Bahn in Germany that is the shortest in Berlin's U-Bahn system, with a length of 2.86 kilometres (1.78 mi). Opened in 1910, the U4 serves five stations, all of which are step-free: it is also the only subway line in Berlin to have never been extended and the only one to have no night service on weekends.

In 1903, Schöneberg, an independent city that as south-west of the municipal limits of Berlin, planned to develop an underground railway line to improve public transportation. As the line promised less profit for private investors (all Berlin U-Bahn lines had until then been built with private capital), negotiations with the Berliner Hochbahngesellschaft (Berlin Elevated Railway Company, the operator of Berlin U-Bahn) were unsuccessful.

That made Schöneberg start to build the line itself on 8 December 1908. Two years later, the construction was finished, and on 1 December 1910, the line was put into operation. Although Schöneberg owned the track, upon the line's opening, the city handed operations over to the Hochbahngesellschaft.