Trams in Berlin

The Berlin tramway (German: Straßenbahn Berlin) is the main tram system in Berlin, Germany. It is one of the oldest tram networks in the world having its origins in 1865 and is operated by Berliner Verkehrsbetriebe (BVG), which was founded in 1929. It is notable for being the third-largest tram system in the world, after Melbourne and St. Petersburg. Berlin's tram system is made up of 22 lines that operate across a standard gauge network, with almost 800 stops and measuring almost 190 kilometres (120 mi) in route length and 430 kilometres (270 mi) in line length. Nine of the lines, called Metrotram, operate 24 hours a day and are identified with the letter "M" before their number; the other thirteen lines are regular city tram lines and are identified by just a line number.
Most of the current network is within the confines of the former East Berlin, as tram lines within West Berlin were replaced by buses during the division of Berlin. However, the first extension into West Berlin opened in 1994 on today's M13. In the eastern vicinity of the city there are also three private tram lines that are not part of the main system; the Potsdam tram system, with its own network of lines, is just to the south-west of Berlin.
In 1865, a horse tramway was established in Berlin. In 1881, the world's first electric tram line was opened in the city. Numerous private and municipal operating companies constructed new routes, so by the end of the 19th century the network had developed quite rapidly, and the horse trams had been replaced by electric ones. By 1930, the network had a route length of over 630 km (391 mi) with more than 90 lines. In 1929, all operating companies were unified into the BVG. After World War II, BVG was divided into an eastern and a western company but was once again reunited in 1992, after the fall of East Germany. In West Berlin by 1967 the last tram lines had been shut down. With the exception of two lines constructed after German reunification, the Berlin tram continues to be limited to the eastern portion of Berlin.
The public transport system of Berlin is the oldest one in Germany. In 1825, the first bus line from Brandenburger Tor to Charlottenburg was opened by Simon Kremser, already with a timetable. The first bus service inside the city operated from 1840 between Alexanderplatz and Potsdamer Bahnhof. It was run by Israel Moses Henoch, who had run the cab service since 1815. On 1 January 1847, the Koncessionierte Berliner Omnibus Compagnie (Concessionary Berlin Bus Company) started its first horse-bus line. The growing market witnessed the launch of numerous additional companies, with 36 bus companies in Berlin by 1864.
On 22 June 1865, the opening of Berlin's first horse tramway marked the beginning of the age of trams in Germany, stretching from Brandenburger Tor along today's Straße des 17. Juni (17 June Road) to Charlottenburg. Two months later, on 28 August, it was extended along Dorotheenstraße to Kupfergraben near today's Museumsinsel (Museum Island), a terminus which is still in service today. Like the horse-bus, many companies took advantage of the new development and built horse-tram networks in all parts of today's urban area. In 1873, a route from Rosenthaler Platz to the Gesundbrunnen was opened, to be operated by the new Große Berliner Pferde-Eisenbahn (Great Berlin Horse Railway) which would later become the dominant company in Berlin under the name of Große Berliner Straßenbahn (GBS; Great Berlin Tramway).
On 16 May 1881, the region of Berlin again made transport history. In the village of Groß-Lichterfelde, which was incorporated into Berlin-Steglitz 39 years later, Werner von Siemens opened the world's first electric tramway. The electric tram in Groß-Lichterfelde was built to 1,000 mm (3 ft 3+3⁄8 in) metre gauge and ran from today's suburban station, Lichterfelde Ost, to the cadet school on Zehlendorfer Straße (today Finckensteinallee). Initially, the route was intended merely as a testing facility. Siemens named it an "elevated line taken down from its pillars and girders" because he wanted to build a network of electric elevated lines in Berlin. But the skeptical town council did not allow him to do this until 1902, when the first elevated line opened.
The first tests of electric traction on Berlin's standard gauge began on 1 May 1882, with overhead supply and in 1886 with batteries, were not very successful. Electric traction of standard-gauge trams in Berlin was definitively established in 1895. The first tram line with an overhead track supply ran in an industrial area near Berlin-Gesundbrunnen station. The first line in a more inhabited area operated with batteries for its first year; a catenary was installed four years later. In 1902, electrification with overhead wiring had been completed, except for a very small number of lines on the periphery.
The last horse-drawn tram line closed in 1910.
On 28 December 1899, it became possible to travel underground, even under the Spree, upon completion of the Spreetunnel between Stralau and Treptow. Owing to structural problems, it was closed on 25 February 1932. From 1916 to 1951, the tram had a second tunnel, the Lindentunnel, passing under the well-known boulevard Unter den Linden.
The history of tram companies of the Berlin Strassenbahn is very complicated. Besides the private companies, which often changed because of takeovers, mergers, and bankruptcies, the cities of Berlin, Spandau, Köpenick, Rixdorf; the villages Steglitz, Mariendorf, Britz, Niederschönhausen, Friedrichshagen, Heiligensee and Französisch Buchholz, and the Kreis Teltow (Teltow district) had municipal tram companies.
The most important private operating company was the Große Berliner Pferde-Eisenbahn (Great Berlin Horse Railway), which called itself Große Berliner Straßenbahn (GBS) (Great Berlin Tramway) after commencing electrification. GBS acquired nearly all of the other companies through the years. In 1920, the GBS merged with the municipal companies BESTAG and SSB to become the Berliner Straßenbahn (Berlin Tramway), which was reorganized in 1929 into the newly formed municipal Berliner Verkehrs-AG (BVG) (Berlin Transport Company). Besides the tramway, the BVG also took over the elevated and underground rail lines and the bus routes which were previously operated primarily by the Allgemeine Berliner Omnibus-Actien-Gesellschaft (ABOAG) (General Berlin Bus Corporation).
The following table includes all companies that operated tramways in today's Berlin before the formation of the BVG. The background color of each line marks the drive method which the respective company used to serve their lines at the time of the formation (blue = horse tram, yellow = steam tram, white = electric tram, red = benzole tram).
On the day of its formation, the BVG had 89 tram lines: a network of 634 km (394 mi) in length, over 4,000 tramway cars, and more than 14,400 employees. An average tram car ran over 42,500 km (26,400 mi) per year. The Berlin tram system had more than 929 million passengers in 1929, at which point, the BVG already had increased its service to 93 tram lines.
In the early 1930s, the Berlin tram network began to decline; after partial closing of the world's first electric tram in 1930, on 31 October 1934, Germany's oldest tram line followed. The Straße des 17. Juni, formerly the Charlottenburger Chaussee, was rebuilt by Nazi planners following a monumental east–west-Axis, and the tramway had to leave. In 1938, however, there were still 71 tram lines, 2,800 tram cars and about 12,500 employees. Consequently, the bus network was extended during this time. From 1933, Berlin also had trolley buses.
During World War II, some transport tasks were given back to the tramway to save oil. Thus an extensive transport of goods was established. Bombings (from March 1943 on) and the lack of personnel and electricity caused the transportation performance to decline. Due to the final Battle for Berlin, the tram system finally collapsed on 23 April 1945. Prior to the battle, many destroyed and gutted trams were turned into makeshift roadblocks (being pushed by civilians/Volkssturm militia) into the middle of streets and mostly filled with piles of building rubble to serve as solid obstacles) through major roads in the city to halt the advance of Soviet tanks and vehicles invading Berlin.
The BVG was—like most other Berlin institutions—split into two different companies on 1 August 1949. Two separate companies were formed, the BVG West in the three western sections (with 36 tram lines) and the BVG Ost (Berlin Public Transit Authority East) (with 13 lines) in the Soviet sector. The latter became in 1969 the VEB Kombinat Berliner Verkehrsbetriebe (BVB). On 14 October 1950, traffic on the lines from West Berlin to the Brandenburgian suburbs Kleinmachnow and Schönefeld ceased; on 15 January 1953, traffic over the downtown sector border followed.
From 1949 to 1955, line by line, both companies replaced the Thomson-Houston type trolley poles of their tramcars with pantographs.
From 1954 onwards, a shift took place with the public transit plans for West Berlin. From that moment, planning aimed at discontinuing the tram service and replacing it with extended underground and bus lines. The tramway system was considered old-fashioned and unnecessary since Berlin already had a well-developed underground network. From 1954 to 1962 numerous tram lines were replaced with bus routes and extended underground lines and stops. By 1962, the western part of the city had only 18 tram lines left out of the original 36.
On 2 October 1967 the final tramcar traveled through West Berlin over the last line, numbered 55—from Zoo Station via Ernst-Reuter-Square, the City Hall in Charlottenburg, Jungfernheide S-Bahn station, Siemensdamm, Nonnendammallee, Falkenseer Platz, and Neuendorfer Allee to Spandau, Hakenfelde.
Today, many MetroBus lines follow the routes of former tram lines.
The division of the city resulted in many problems and difficulties for the public transportation system. Tram lines could no longer operate through the city center, and the main tram depot was moved to Uferstraße in Western Berlin.
Soviet Moscow, with its tram-free avenues, was the role model for East Berlin's transport planning. The car-oriented mentality of West Berlin also spread in the East, with many tram lines also closing in the latter in the 1950s and 1960s. In 1967, the lines through the city center closed down at the same time as the new city expansion around Alexanderplatz was starting to develop.
However, a complete elimination of the city's tram network was neither planned nor even discussed.
The following streets were constructed in order to connect the new housing estates Marzahn, Hohenschönhausen, and finally Hellersdorf to the city's tram network from the late 1970s to the early 1990s:
Some streets were closed, especially those too close to the Berlin Wall:
In 1992, the West Berlin transport company BVG took over East Berlin's BVB. (In addition to bus and U-Bahn lines, the new BVG also ran the trams, by now only operating in the former East Berlin districts).
There was an attempt to shut down the tram routes running to Pankow, because the trams in Schönhauser Allee run parallel to the U2 line, though the latter does not run to Rosenthal. However, in line with other tram networks expanding at that time, plans for network expansions were soon made - some of those across the now-abolished border into West-Berlin.
In 1995, the first stretch of the tram route along Bornholmer Straße was opened to the west in two stages. The Rudolf-Virchow-Klinikum and the metro stations located in Seestraße, Wedding, and Osloer Straße in Gesundbrunnen have since re-connected to the tram network.
Since 1997, the tram has stopped right at Friedrichstraße station. Previously, passengers changing between modes of transport here had to take a long walk to get to the restored train station. Since then, trams have terminated along the reversing loop "Am Kupfergraben" near Humboldt University and Museum Island.
The following year saw the re-opening of tram facilities at Alexanderplatz. These routes now arrive directly from the intersection with Otto-Braun-Straße across the square, stopping both at the U2 underground station and the overground station for regional and commuter trains, where there is a direct interchange to the U5 and U8 lines. An increase in tram accidents in pedestrian zones was feared by critics but did not materialize.
In 2000, the tram tracks were extended from the previous terminus at Revalerstraße, past the Warschauer Straße S-Bahn station to the U-Bahn station of the same name. Since there is no room for a return loop, a blunt ending track was built. In order to accomplish this, bi-directional vehicles were procured. However, the tracks, which were further extended in 1995 to the Oberbaumbrücke, have not yet been expanded to Hermannplatz, as had been planned.
Since 2000, the tram in Pankow has run beyond the previous terminus Pankow Kirche on to Guyotstraße, connecting the local development areas to the network.
On 12 December 2004, BVG introduced the BVG 2005 plus transport concept. The main focus was the introduction of Metrotram or Metrobus lines on very busy routes which have no U-Bahn or S-Bahn lines. On the tram network, therefore, nine MetroTram lines were introduced and the remaining lines were partially rearranged. The numbering scheme is based on that from 1993, but has undergone minor adjustments. MetroTram and MetroBus lines have an "M" in front of the line number.
Single MetroTram/MetroBus lines operate on the main radial network. As a rule, the line number corresponds to that of 1993: the M4 from lines 2, 3, and 4, the M5 from line 5, and so on. In addition, the two Pankow lines 52 and 53 were included as line M1 in the scheme. The supplementary lines of these radials continue to be numbered from 10 to 19, unless they augment the respective metro service. Metro services of the ring and tangential net received a number in the range 10–19; the supplementary lines retained a number in the range of 20–29. An exception is the subsequently established line 37, which, together with lines M17 and 27, travels a common route. Of the lines numbered 50–59 the only one remaining was the 50; the lines numbered 60–69 remained largely unaffected by the measures. The then-new lines operated as follows:
Termini in italics above have been subject to change, further information about the current termini is given below.
In 2006, a second line was opened in the western part of the city, and the M10 line was extended beyond its former terminus Eberswalderstraße [de] along Bernauer Straße in Gesundbrunnen to Berlin Nordbahnhof in the district of Mitte, before being further extended to Berlin Hauptbahnhof in 2015.
In May 2007, a new line from Prenzlauer Tor [de] along Karl-Liebknecht-Straße towards Alexanderplatz was put into operation, where the line M2 leads directly to the urban and regional train station instead of the current service via Rosa-Luxemburg-Platz to Hackescher Markt. The previous route along Alt and Neu Schönhauser Straße no longer carries regular services but operates only as a feeder line.
On 4 September 2011, a one-and-a-half-kilometer-long new line from the Adlershof S-Bahn station was opened. It runs from the Adlershof science and business hub (WISTA) to the provisional terminus provisional terminus Karl-Ziegler-Straße [Wikidata] at the Adlershof campus of the Humboldt University of Berlin. The route, with three newly built stops, cost 13 million euros and was first serviced by lines 60 and 61 at overlapping 10-minute intervals. Since 13 December 2015, line 63 has run to Karl Ziegler Street, replacing line 60. The connection was originally planned for completion in 1999. However, the plan approval procedure was only completed in 2002. Shortly before the plan approval decision expired after five years, the project was approved on 9 August 2007, and soon after the first masts for the overhead line were set up. It was expected to carry 9,000 passengers per workday. On 31 October 2021, it was again extended from Karl-Ziegler Straße, via Landschaftspark Johannisthal [de] to Schöneweide [de] via the Groß-Berliner Damm [de].
There are also some minor closures:
At the timetable change on 14 December 2014, a new tram line was opened from Naturkundemuseum to Hauptbahnhof via Invalidenstraße, with the final stop at Lüneburger Straße in the district of Alt-Moabit. The double-track line is 2.3 kilometers long to the main station, and new stops have been built on the Chausseestraße, the Invalidenpark and the Hauptbahnhof. This is followed by the 1.1 km single track block bypass that has three stops at Lesser-Ury-Weg, Lueneburger Straße and Clara Jaschke-Straße, as well as the installation area. The planned opening date has already been postponed several times. Originally planned to complete in 2002. However, the plan was caught by the Administrative Court in 2004 and revised to either 2006 and 2007. However, the first 80 metres of the track has already been built during the construction of Berlin Hauptbahnhof.
A new approval procedure was completed on 15 January 2010. In April 2011, the preparatory construction work had begun. The Ministry of Transport revised the 50 metres of the length, a two-meter-wide strip of garden to the state of Berlin to provide enough space for all road users. In the course of the work on the new line sector, the line branch along, Chausseestraße (between Invalidenstraße and Wöhlertstraße), Schwartzkopffstraße, Pflugstraße, Wöhlertstraße was permanently closed on 26 August 2013. The commissioning of the new line was initially only with the line M5. With the restoration of the connection from the Nordbahnhof to the underground station Naturkundemuseum, the new line from 28 August 2015 could also be used by the lines M8 and M10.
In 2023 work on increasing the supply voltage from 600 V to 750 V was completed.
The first horse-drawn tramlines did not use any special labeling as they were radially inferior from the respective endpoints in the center and thus had few points of contact with other lines. Only with the expansion of the network into the city center was there a need to distinguish the lines from each other. From the 1880s, most major German cities therefore used colored target signs or signal boards, sometimes both together. In Berlin, these were always kept in the same combination. As identification colors red, yellow, green and white were used, from 1898 additionally blue. The panels were one or two colors, the latter either half / half divided or in thirds with a line in the second color. However, the number of signal panels used was not sufficient to equip each line with its own color code. In addition, crossing or side by side lines should run with different signal panels. This meant that individual lines had to change their color code several times in the course of their existence. As a result of the electrification and the takeover of the New Berlin Horse Ride by the Great Berlin Horse Railways / Great Berlin Tram (GBPfE / GBS) increased their number of lines at the turn of the century abruptly. With a view of the Hamburg tram, where in the summer of 1900 for the first time in German-speaking countries line numbers were introduced, experimented the GBS from 1901 also with the numbers. In the timetables of this time, the lines were numbered, but could change their order every year. The numbering scheme should include not only the GBS but also its secondary lines. At the same time, letter-number combinations as they appeared in the timetable booklet should be avoided.
The scheme introduced on 6 May 1902 was relatively simple: single numbers were reserved for the ring lines, two-digit for the remaining lines. Initially, the tens gave information about where the line was going; 10 lines were to be found in Moabit, 60 lines in Weissensee and 70 lines in Lichtenberg. The lines of the West Berlin suburban railway were assigned the letters A to M, the Berlin-Charlottenburg tram the letters N to Z and the lines of the Southern Berlin suburban railway were numbered with Roman numerals. The 1910 taken over by the GBS northeastern Berliner Vorortbahn received in 1913 the line designation NO. The colored signal panels remained in parallel until about 1904. In addition, the lines created during this period were still colored signal panels with new, sometimes even three-color color combinations.
Insertors were marked separately from the March 1903. They bore the letter E behind the line number of their main line. In later years, these lines increasingly took over the tasks of booster drives and were therefore shown in the timetables as separate lines. On 15 April 1912, the GBS introduced the first line with three-digit number. The 164 was created by extending the 64, which was maintained in parallel. In the following months more lines were provided with 100 numbers or newly set up, usually as a line pair to the existing line.
The surrounding businesses were not affected by the change in May 1902 and set on their own markings. The lines of the urban trams and the meterspurigen lines of the Teltower circular orbits were still marked with signal panels, on the other hand, the BESTAG and in Heiligensee, not the lines, but only the targets were marked with different colored signs. In 1908, the Spandauer Straßenbahn introduced the line identification with letters, which corresponded to the initial letter of the destination (line P to Pichelsdorf, etc.), in 1917 the company switched to numbers. In Cöpenick, the lines were marked from 1906 with numbers, from 1910 additionally with colored signal panels for the individual routes (red lines to Friedrichshagen, etc.). The Berlin Ostbahnen used from 1913 also like the SBV Roman numbers as line numbers. The other companies, including the standard-gauge lines of the Teltower Kreisbahnen, did not use a line marking.
With the merger of companies for the Berlin tram, the GBS's numbering scheme was extended to cover the rest of the network. Usually, those numbers are assigned, whose lines were continued during the World War I. For example, it came about that the lines operating in Köpenick received mainly 80s numbers. Letters were still awarded to the tram lines in the BVG until 1924, after which it was reserved for the suburban tariff buses.
With the outbreak of the Second World War, the Berlin public transport companies had to stop a large part of the bus traffic to save fuel. Tram traffic has been extended accordingly. The newly established amplifier lines contributed to the distinction of the master lines 200 and 300 numbers. From 1941, the night routes of the bus and the tram networks were later classified into the 400-series numbers. The measures were existed until the end of the war. The last 100 numbers were renumbered on 31 May 1949.
After the administrative separation of the BVG initially only changed the numbering scheme. Tram lines running from the east to the west of Berlin kept their number after the grid separation in 1953 and as a result of network thinning, individual lines were disappeared. The BVG-West waived from July 1966, the prefix A on the bus lines, the BVG-Ost waived on 1 January 1968. While in the west tram traffic was stopped 15 months later, the passenger in the east could not tell from the line number whether it was a tram or bus line. The Berliner Verkehrsbetriebe therefore planned to systematise their network in the 1970s. The city center lines of the tram should receive the line numbers 1 to 30, in Köpenick should retain their 80s numbers. The remaining numbers were intended for the bus. Night lines received from 1973 uniformly 100 numbers, for the tram were initially provided only the numbers from 120. The conversion of the daily lines was only partially completed.
After the reunification, in two steps, a uniform numbering scheme was introduced, which included the lines in the state of Brandenburg. The Berlin tram was assigned the line number range from 1 to 86, then followed by the overland operations in Woltersdorf, Schöneiche and Strausberg with the numbers 87 to 89. The Potsdam tram received the 90s line numbers. E-lines were no longer listed separately in the timetable, but the amplifiers continued to operate as such until 2004. Night lines were indicated on both means of transport by a preceding N and the three-digit line numbers were henceforth intended for the bus routes. The first conversion of 2 June 1991 followed the Berlin tram lines on 23 May 1993. The network was reorganized and divided into five number ranges. The main focus was on the focus on the historical center. Single lines formed the radial main network, 10 lines their supplementary network. 20er lines were intended for the ring and Tangentiallinien. There were 50 lines in the district of Pankow, 60 lines in the district of Köpenick analogous to the bus lines there.
BVG had instituted a new line structure, where the BVG has 22 lines since 2004. MetroTram also uses the symbol . On 12 December 2004, BVG had introduced the transport concept, BVG 2005+. The main content was the introduction of metro lines on busy routes where there are no S-Bahn or U-Bahn. In the tram network, therefore, nine tram lines under MetroTram were introduced, and the other lines have permanently rearranged. The numbering scheme is that it was similar to the 1993 scheme, but has undergone major adjustments.
Metro lines with a single digit number travel through the radial main network, as a rule, the line number corresponds to that of 1993, so the lines became 2, 3, and 4 into M4, the 5 into M5 and so on. In addition, the two Pankow lines, 52 and 53 were included as line M1 in the main scheme. The supplementary lines of the radials continue to carry 10 numbers, unless they have been merged into the amplifier of the metro line. Metro lines of the ring and tangential network received the numbers in the 10 range, whose supplementary lines retain the 20 range. An example is the retrofitted line, route 37, which together with the lines of M17 and 27 runs a common route. Of the 50 routes remained, the only one of the 50, the 60 lines were remained untouched by these measures.
Tram line 68 was named by the National Geographic Society as one of the ten great streetcar routes worldwide.
Since December 2016, Berlin has planned major light rail expansion which has been revived. Earlier plans has been there since 2000 for completion between 2005 and 2010. There will be no tramway closures.
Four tram projects already under development by BVG were being prioritised for construction with work beginning from 2017 to 2021, with only the first two of the four starting construction in said time span. The other two have had construction delayed for a later time.
Five more tram lines will also be developed and construction will begin after 2021; these will see trams returning to parts of inner West Berlin for the first time since the 1960s, in addition to the already dense network expansion in the city. These include:
These are the long-term plans after 2026, which will see more direct tram networks in the West Berlin area:
Further long-term plans after 2031:
In Johannisthal a route over the Sterndamm and the Stubenrauchstraße to the subway station at Zwickauer Damm in Rudow, or to the subway station at Johannisthaler Chaussee, has been proposed. This route serves the residential areas around the Zwickauer Damm and the Eisenhutweg, making for a better public transport connection. For this route, space was reserved for the tram tracks as a preliminary step in the construction of the Hermann-Gladenbeck Bridge over the A-113 and the Massantenbrücke over the Teltowkanal 2004. Likewise, the existing track bed of the Neukölln-Mittenwalder railway can be used behind the Massantenbrücke or Hermann-Gladenbeck bridge, which is just a short distance behind the underground station at Zwickauer Damm.
Until 2006, there were deliberations to suspend parts of lines M1, M2, 12, 27, 60, and 61 as soon as the parts of the road, then considered unprofitable, were to be renewed for further operation. However, these were not realized, in fact, some of the mentioned routes have now been refurbished, the headways have been consolidated on them, or, as already mentioned, there are even plans for extensions.
Berlin's tram system has two different families of vehicles. There are low floor six-axle double articulated GTU, GTO and GTZO (formerly GT6N and GT6N-ZR) trams in unidirectional and bidirectional versions, and since 2008, the Bombardier Flexity Berlin.
The Tatra KT4 trams were phased out by 2021, and the Communist-era T6A2/B6A2 trams were phased out by 2007.
The number of trams has shrunk continuously. The BVB had 1,024 vehicles, while currently there are about 600. The reduction is possible because the new low-floor cars on average achieve more than twice the mileage per year (100,000 km (62,137 mi)), and, being longer, carry more passengers and therefore rarely operate in multiple.
In July 2006, the cost of energy per vehicle-kilometer was:
Between 1992 and 2003 45 bidirectional GT6N-ZRs and 105 unidirectional GT6Ns were purchased. The cars have a width of 2.30 m (7 ft 7 in) and a length of 26.80 m (87 ft 11 in). They can carry 150 passengers and can run as coupled sets.
134 cars were leased to a US investor and leased back. The SNB has accrued more than €157 million ($205 million) to hedge potential losses from cross-border business.
In the end of 2011 and beginning of 2012 the SNB began the upgrading of 1006 and 1016 as a sample exercise. They were provided with a new drive technology and new software such as the Flexitys. The only mutually detachable vehicles are distinguished by new car numbers 1506 and 1516. After completion of the first two the BVG ordered the upgrading of all other cars of the GT6N and GT6N-ZR cars.
Identically to 1506 and 1516 the first 77 cars were provided with a new drive technology and new software and upgraded to type GTU trains in the years 2012 – 2016. All GTU trains got increased car numbers by +500. The new car numbers are 1502 – 1605 (with gaps).
The rest of the GT6N and all of the GT6N-ZR got a new on-board-unit instead, upgrading them to type GTO and GTZO in the years 2016 – 2017. Their numbers were increased by +200. The new car numbers are 1201 – 1263 (with gaps) for the GTO and 2201 – 2245 for the GTZO.
In April 2005, a European tender was issued for low floor trams, half unidirectional, and half bidirectional vehicles. The latter will respond better to the BVG and construction faults and build on certain routes for cost savings. The Vienna tramway tram type ULF was tested in passenger service.
On 12 June 2006, the BVG decided to procure new trams. These are based on the tested Incentro, referred to by Bombardier as Flexity Berlin. In October 2008, for €13 million ($17 million), four prototypes were ordered and since then extensively tested. There are one- and two-way cars, respectively 30.8 m (101 ft 1 in) and 40 m (131 ft 3 in) in length, carrying about 180 or 240 passengers. Use in coupled sets is not possible.
On 29 June 2009, the supervisory board of the BVG decided to buy 99 Flexity cars, 40 of which will be long and 59 short versions, for €305.3 million ($397.9 million). In September 2011 the first 13 long cars began to be delivered. To replace all old Tatra cars, a further 33 costing €92.3 million ($120.3 million) may need to be ordered in 2017. The trams will be manufactured at Bombardier's Bautzen works or Hennigsdorf.
In June 2012 the supervisory board approved the BVG 2nd Serial recall of an additional 39 trams of type "Flexity Berlin". Considering the order of over 99 vehicles from 2010, that means a total of 38 vehicles and 47 long bidirectional vehicles, as well as 53 short bidirectional vehicles will be ordered from the manufacturer, Bombardier Transportation. Thus, the SNB responds to both the very positive development of passenger numbers at the tram and allows bidirectional vehicles the eventual abandonment of turning loops and enhancing the design stops. Once this procurement is secured in 2017, then the old Tatra cars can be scrapped. The State of Berlin's funded budget is €439.1 million ($572.7 million).
The new cars have 2.4 m (7 ft 10 in) wheel spacing, 10 cm (3.9 in) longer than the existing low-floor trams. The track width was chosen so that modifications in the network are not necessary This affects only the routes upon which the Flexities will be operated. They are unable to run in Köpenick and on parts of the network in Pankow.
In December 2015, BVG exercised an option for another 47 Flexity trams from Bombardier to handle increased ridership.
Depots are required for stabling and maintenance purposes. BVG has seven operational tram depots, five of which are used for stabling service trams:
Out-of-service trams returning to Nalepastraße and Weissensee depot remain in-service until reaching the special tram stop at each depot.
Around Berlin there are some additional tram systems that do not belong to the BVG but are integrated with the greater VBB system:
The last three companies are located in the eastern suburbs at the eastern edge of Berlin. Each of them has only one line.