. at the beginning of the 20th century By 1845, Paris and the railway companies were already thinking about an urban railway system to link inner districts of the city. The railway companies and the French government wanted to extend mainline railways into a new underground network, whereas the Parisians favoured a new and independent network and feared national takeover of any system it built. The disagreement lasted from 1856 to 1890. Meanwhile, the population became denser and traffic congestion grew massively. The deadlock put pressure on the authorities and gave the city the green light. Prior to 1845, the urban transport network consisted primarily of a large number of omnibus lines, consolidated by the French government into a regulated system with fixed and unconflicting routes and schedules. The first concrete proposal for an urban rail system in Paris was put forward by civil engineer Florence de Kérizouet. This plan called for a surface
cable car system. In 1855, civil engineers Edouard Brame and
Eugène Flachat proposed an underground freight urban railway, due to the high rate of accidents on surface rail lines. On 19 November 1871 the General Council of the Seine commissioned a team of 40 engineers to plan an urban rail network. This team proposed a network with a pattern of routes "resembling a cross enclosed in a circle" with axial routes following large boulevards. On 11 May 1872 the Council endorsed the plan, but the French government turned down the plan. After this point, a serious debate occurred over whether the new system should consist of elevated lines or of mostly underground lines; this debate involved numerous parties in France, including
Victor Hugo,
Guy de Maupassant, and the Eiffel Society of
Gustave Eiffel, and continued until 1892. Eventually the underground option emerged as the preferred solution because of the high cost of buying land for rights-of-way in central Paris required for elevated lines, estimated at 70,000 francs per metre of line for a -wide railway. The last remaining hurdle was the city's concern about national interference in its urban rail system. The city commissioned renowned engineer
Jean-Baptiste Berlier, who designed Paris's postal network of pneumatic tubes, to design and plan its rail system in the early 1890s. Berlier recommended a special
track gauge of (versus the
standard gauge of ) to protect the system from national takeover, which inflamed the issue substantially. The issue was finally settled when the Minister of Public Works begrudgingly recognised the city's right to build a local system on 22 November 1895, and by the city's secret designing of the trains and tunnels to be too narrow for mainline trains, while adopting standard gauge as a compromise with the state.
Fulgence Bienvenüe project , 1903 On 20 April 1896, Paris adopted the
Fulgence Bienvenüe project, which was to serve only the city proper of Paris. Many Parisians worried that extending lines to industrial suburbs would reduce the safety of the city. Paris forbade lines to the inner suburbs and, as a guarantee, Metro trains were to run on the right, as opposed to existing suburban lines, which ran on the left. Unlike many other subway systems (such as that of London), this system was designed from the outset as a unified system, initially of nine lines. Such a large project required a private-public arrangement right from the outset – the city would build most of the permanent way, while a private concessionaire company would supply the trains and power stations, and lease the system (each line separately, for initially 39-year leases). In July 1897, six bidders competed, and The Compagnie Generale de Traction, owned by the Belgian
Baron Édouard Empain, won the contract; this company was then immediately reorganised as the
Compagnie du chemin de fer métropolitain. Construction began in November 1898. The first line,
Porte Maillot–
Porte de Vincennes, was inaugurated on 19 July 1900 during the
Paris World's Fair. Entrances to stations were designed in
Art Nouveau style by
Hector Guimard. Eighty-six of his entrances are still in existence. Bienvenüe's project consisted of 10 lines, which correspond to current Lines 1 to 9. Construction was so intense that by 1920, despite a few changes from schedule, most lines had been completed. The shield method of construction was rejected in favor of the cut-and-cover method in order to speed up work. Bienvenüe, a highly regarded engineer, designed a special procedure of building the tunnels to allow the swift repaving of roads, and is credited with a largely swift and relatively uneventful construction through the difficult and heterogeneous soils and rocks.
Line 1 and
Line 4 were conceived as central east–west and north–south lines. Two lines,
ligne 2 Nord (Line 2 North) and
ligne 2 Sud (Line 2 South), were also planned but Line 2 South was merged with
Line 5 in 1906.
Line 3 was an additional east–west line to the north of line 1 and line 5 an additional north to south line to the east of Line 4.
Line 6 would run from
Nation to
Place d'Italie. Lines
7,
8 and
9 would connect commercial and office districts around the
Opéra to residential areas in the north-east and the south-west. Bienvenüe also planned a circular line, the
ligne circulaire intérieure, to connect the six mainline stations. A section opened in 1923 between
Invalides and the
Boulevard Saint-Germain before the plan was abandoned.
Nord-Sud competing network On 31 January 1904, a second concession was granted to the
Société du chemin de fer électrique souterrain Nord-Sud de Paris (Paris North-South underground electrical railway company), abbreviated to the
Nord-Sud (North-South) company. It was responsible for building three proposed lines: • Line A would join
Montmartre to
Montparnasse as an additional north–south line to the west of Line 4. • Line B would serve the north-west of Paris by connecting
Saint-Lazare station to Porte de Clichy and Porte de Saint-Ouen. • Line C would serve the south-west by connecting
Montparnasse station to
Porte de Vanves. The aim was to connect Line B with Line C, but the CMP renamed Line B as
Line 13 and Line C as
Line 14. Both were since conjoined by the RATP as the current Line 13. Line A was inaugurated on 4 November 1910, after being postponed because of floods in January that year. Line B was inaugurated on 26 February 1911. Because of the high construction costs, the construction of line C was postponed. Nord-Sud and CMP used compatible trains that could be used on both networks, but CMP trains used 600 volts third rail, and NS −600 volts overhead wire and +600 volts third rail. This was necessary because of steep gradients on NS lines. NS distinguished itself from its competitor with the high-quality decoration of its stations, the trains' extreme comfort and pretty lighting. Nord-Sud did not become profitable and bankruptcy became unavoidable. By the end of 1930, the CMP bought Nord-Sud. Line A became
Line 12 and Line B
Line 13. Line C was built and renamed
Line 14, then was reorganised in 1937 alongside Lines 8 and 10. This former line 14 is now the southern part of Line 13. The last Nord-Sud train set was decommissioned on 15 May 1972.
1930–1950: first inner suburbs are reached Bienvenüe's project was nearly completed during the 1920s. Paris planned three new lines and extensions of most lines to the inner suburbs, despite the reluctance of Parisians. Bienvenüe's inner circular line having been abandoned, the already-built portion between Duroc and Odéon for the creation of a new east–west line that became
Line 10, extended west to Porte de Saint-Cloud and the inner suburbs of
Boulogne. The line C planned by Nord-Sud between Montparnasse station and
Porte de Vanves was built as
Line 14 (different from
present Line 14). It extended north in encompassing the already-built portion between Invalides and Duroc, initially planned as part of the inner circular. The saturated
Belleville funicular tramway would be replaced by a new line,
Line 11, extended to
Châtelet. Lines 10, 11 and 14 were thus the three new lines envisaged under this plan. Most lines would eventually be extended to the inner suburbs. The first to leave the city proper was Line 9, extended in 1934 to
Boulogne-Billancourt; followed by Lines 12 south and 1 east in 1934. World War II forced authorities to abandon projects such as the extension of Lines 4 and 12 to the northern suburbs. By 1949, eight lines had been extended: Line 1 to
Neuilly-sur-Seine, Line 3 to
Levallois-Perret, Line 5 to
Pantin, Line 7 to
Ivry-sur-Seine, Line 8 to
Charenton, Line 9 to Boulogne-Billancourt, Line 11 to
Les Lilas and Line 12 to
Issy-les-Moulineaux. World War II had a massive impact on the Metro. Services were limited and many stations closed. The risk of bombing meant the service between
Place d'Italie and
Étoile was transferred from Line 5 to Line 6, so that most of the elevated portions of the Metro would be on Line 6. As a result, Lines 2 and 6 now form a circle. Most stations were too shallow to be used as bomb shelters. The
French Resistance used the tunnels to conduct swift assaults throughout Paris. It took a long time to recover after liberation in 1944. Many stations, such as
Liège, had not reopened by the 1960s while some others, such as
Champ de Mars and
Saint-Martin, never reopened. On 23 March 1948, the CMP (the underground) and the STCRP (bus and tramways) merged to form the
RATP, still running the Metro and most of Paris's public transportation services today.
1960–1990: development of the RER , crossing the
Seine, is used by Line 5 The network grew saturated during the 1950s. Outdated technology limited the number of trains, which led the RATP to stop extending lines and concentrate on modernisation. The
MP 51 prototype was built, testing both
rubber-tyred metro and basic automatic driving on the
voie navette. The first replacements of the older Sprague trains began with experimental articulated trains and then with mainstream rubber-tyred Metro
MP 55 and
MP 59, some of the latter having only retired in 2025. Thanks to newer trains and better signalling, trains ran more frequently. The population boomed from 1950 to 1980. Car ownership became more common and suburbs grew further from the centre of Paris. The main railway stations, termini of the suburban rail lines, were overcrowded during rush hour. The short distance between Metro stations slowed the network and made it unprofitable to build extensions. The solution in the 1960s was to revive a project abandoned at the end of the 19th century: joining suburban lines together through new express underground portions in the city centre : the
Réseau Express Régional (regional express network; RER). , modernized at the arrival of Line 14 during the 2000s. The RER plan initially included one east–west line and two north–south lines. RATP bought two unprofitable SNCF lines—the Ligne de Saint-Germain (westbound) and the Ligne de Vincennes (eastbound) with the intention of joining them and to serve multiple districts of central Paris with new underground stations. The new line created by this merger became Line A. The Ligne de Sceaux, which served the southern suburbs and was bought by the CMP in the 1930s, would be extended north to merge with a line of the
SNCF and reach the new
Charles de Gaulle Airport in Roissy. This became
Line B. These new lines were inaugurated in 1977 and their wild success outperformed the most optimistic forecasts, so much so that RER line A is the most used urban rail line in Europe with nearly 300 million journeys a year. Because of the enormous cost of these two lines, the third planned line was abandoned and the authorities decided that later developments of the RER network would be more cheaply developed by the SNCF, alongside its continued management of other suburban lines. However, the RER developed by the SNCF would never match the success of the RATP's two RER lines. In 1979, the SNCF developed
Line C by joining the suburban lines of the
Gare d'Austerlitz and
Gare d'Orsay, the latter being converted into a museum dedicated to impressionist paintings. During the 1980s, it developed
Line D, which was the second line planned by the initial RER schedule, but serving Châtelet instead of
République to reduce costs. A huge Metro-RER hub was created at
Châtelet–Les Halles, becoming one of the world's largest underground stations. The same project of the 1960s also decided to merge subway Lines 13 and 14 to create a quick connection between Saint-Lazare and Montparnasse as a new north–south line. Distances between stations on the lengthened line 13 differ from that on other lines in order to make it more "express" and hence to extend it farther in the suburbs. The new
Line 13 was inaugurated on 9 November 1976.
1990–2010: Eole and Météor on Line 1, refurbished in the late 2000s In October 1998, the current day
Line 14 was inaugurated on its central trunk (from
Saint-Lazare to
Bibliothèque François Mitterrand stations). It was the first fully new Metro line in 63 years. Known during its conception as
Météor (MÉTro Est-Ouest Rapide), it was the first of the now three fully automatic lines within the network, along with Lines 1 and 4. It was also the first line of the Parisian network to feature
platform screen doors on every station on opening day to prevent suicides and accidents. It was conceived with suburban extension in mind, similar to the Line 13 extensions built during the 1970s. As a result, most of the stations are at least a kilometre apart. Like the RER lines designed by the RATP, nearly all stations offer connections with multiple Metro lines. Lines 13 and 7 are the only two on the network to be split in branches. Hoping to get rid of those saturated branches and thus improve the network's efficiency, RATP had initially planned to attribute to line 14 one branch of each line (most probably the Asnières-Gennevilliers and Villejuif branches), then extend them both further into the suburbs. This project was abandoned due to the cost of modernizing the allotted branches. In 1999, the
RER Line E was inaugurated. Known during its conception as Eole (Est-Ouest Liaison Express), it is the fifth RER line. Originally terminating at station, it was extended west in early 2025 towards Nanterre, through the
La Défense business district, with an extension west through "stealing" the Mantes-la-Jolie branch of Transilien line J, in mind and on papers.
2010 and beyond: automation , opened in 2011 Between 2007 and November 2011, Line 1 was converted to driverless operation. The line was operated with a combination of driver-operated trains and driverless trains until the last driverless
MP 05 train joined in February 2013. The same conversion for Line 4 was completed on 13 January 2022, with the last non-automatic train removed from that line to Line 6 on 17 December 2023, with plans to automate Line 13.
Line 14 was automated from Day 1, as will the upcoming lines 15 to 18 part of the
Grand Paris Express. Several of the historic lines were extended through the suburbs since 2010 : • Line 8 was extended one station southeast to
Pointe du Lac in 2011, • Line 12 was extended one station northeast to
Aubervilliers in 2012, then two more stations further northeast in 2022. • Line 4 was extended to
Mairie de Montrouge in 2013 then to
Bagneux–Lucie Aubrac station in 2022, • Line 14 was extended by northbound to
Mairie de Saint-Ouen in December 2020 then
Saint-Denis–Pleyel station in 2024, before opening a 14 km expansion southbound towards the
Orly Airport in 2024. • Line 11 was extended 6km east to
Rosny–Bois-Perrier station in 2024, marking the first extension on this line for over a century.
Accidents and incidents • 10 August 1903: the
Couronnes Disaster (fire caused by
short circuit), 84 killed. Use of steel for train carriages made mandatory as a result. • 8 February 1962:
Charonne subway massacre, a case of
police brutality committed by the
French police, 9 killed. • July – October 1995:
Paris Metro bombings (terror attack), committed by
Algerian extremists – 8 killed and more than 100 injured. • 30 August 2000: an
MF 67 train derailed due to excessive speed and unavailable automatic cruising through the
Notre-Dame-de-Lorette hairpin, 24 slightly injured. • 6 August 2005: fire broke out on a train at
Simplon, injuring at least 19 people. Early reports blamed an electrical short-circuit as the cause. • 29 July 2007: a fire started on a train between
Varenne and
Invalides. Fifteen people were injured. • 2 December 2016: an MF01 train derailed outside of
Barbès-Rochechouart station on line 2. No casualties were reported. • 17 September 2019: an
MP 05 train skipped three stations from
Concorde to
Franklin D. Roosevelt. It finally came to a stop at
George V station. Even though nobody was hurt, several passengers were terrified. A bang was also reported to be heard at
Palais Royal-Musée du Louvre station. • 14 June 2023: five trains on
Line 4 were shut down. An operational incident on one train is believed to be the cause. Passengers opened the doors and walked along the rails to the nearest station. The evacuation of the blocked trains ended at 9:30 p.m. This incident sparked numerous reactions on social networks, particularly Twitter, where several stranded users expressed their dissatisfaction due to the lack of rapid intervention by the RATP agents and the temperature approaching 35 °C. Traffic resumed around 10:15 p.m. with heavy disruptance. The RATP announced the opening of an internal investigation. ==Network==