Istanbul Metro Network history from Ottoman plans to driverless lines

The first serious plan for an underground railway in Istanbul appeared in 1860, when French engineer Eugène Henri Gavand pitched a tubular tunnel beneath the Bosphorus to link the European and Asian shores. Ottoman authorities studied his drawings and shelved the scheme for lack of capital. Half a century later, the idea resurfaced in a 1910 map drawn by a Franco-Belgian consortium proposing fifty stations across both continents.

When the Republic of Turkey was proclaimed in 1923, planners inherited a crowded city of wooden houses, horse-drawn trams, and ferries crossing between Üsküdar and Eminönü. Engineers from Berlin, Paris, and Rome submitted revised proposals through the 1930s, 1940s, and 1950s, but no municipal budget could cover the cost of boring tunnels beneath a peninsula packed with mosques and buried aqueducts.

Australians first encountered the idea of a Bosphorus crossing in travel writing rather than technical documents. Sydney-siders following the news in the early 2010s read about Marmaray in the same breath as Brisbane's Cross River Rail, with journalists comparing both as bold sub-river projects. With direct flights from Australia now reaching Istanbul in well under a day, the metro's history has become a regular footnote for tour operators Down Under.

Earliest proposals and Ottoman ambitions

The 1860 Gavand scheme envisioned a sunken iron tube resting on the seabed, an approach later used for the Channel Tunnel in a different century. Sultan Abdülaziz approved a feasibility commission but withdrew funding after advisors argued the project would weaken the empire's reputation for fiscal discipline. An Italian engineer named Andrea Bonaiuto later sketched an electric underground railway along the Golden Horn, a plan that won an award at a Paris exhibition.

By 1910, the most ambitious scheme came from the Belgian engineer Léon Gendre and a French banker named Henri Prost. Their network included a circular line beneath the historic peninsula, branch lines reaching Şişli, Beşiktaş, and Üsküdar, and a freight tunnel connecting the Haydarpaşa and Sirkeci terminals. World War I and the collapse of the Ottoman economy ended the project, though the documents survived in the archives of Istanbul University.

Republican-era planning and postwar studies

After 1923, French and German consultants continued to deliver reports that gathered dust on ministry shelves. A 1936 master plan by Henri Prost reserved rights-of-way for a north-south metro line beneath Atatürk Boulevard. Tramway ridership grew past one million passengers a day in the early 1950s, yet officials in Ankara preferred to fund intercity rail rather than urban tunnels.

By the late 1960s, the municipality commissioned a feasibility study from a British consultancy, which concluded that an underground railway was technically feasible but financially unrealistic. A 1976 report from a Japanese team proposed a three-line starter network, again shelved because no international lender would back a city that lacked a single kilometre of operational metro. For Australian readers familiar with how Melbourne's City Loop was debated for decades before construction finally began in 1971, the Turkish delays will sound familiar.

Construction begins under Mayor Dalan

The breakthrough came in 1987 when the municipal administration signed a contract with a Swedish firm to bore the first metro segment. Tunneling machines began chewing through limestone beneath Aksaray in February 1988, working around a labyrinth of Byzantine cisterns and Ottoman foundations. The project was funded by foreign loans denominated in US dollars, municipal bonds, and a national treasury allocation.

Workers paused frequently to reinforce unstable sections, and archaeologists were called in whenever the cutter heads uncovered fragments of the old city walls or the Valens Aqueduct. By 1989, test trains rolled between Aksaray and Kartaltepe, and a fleet of grey-and-blue carriages arrived by ship through the Sea of Marmara. The project consumed six years and a sum that, in today's Australian dollar terms, would sit close to four billion.

The first lines open: M1 and M2

The M1 line, running from Aksaray southward to the airport corridor, opened on 3 September 1989, with free rides for the first week to entice nervous commuters. The line was extended through the 1990s, reaching Esenler in 1994 and later adding branches to Atatürk Airport and the Otogar coach terminal. By the time it reached twenty-six kilometres, M1 carried hundreds of thousands of passengers daily, becoming the workhorse of the European side's industrial suburbs.

The M2 line opened in 2000, eventually connecting Taksim with the business districts of Levent and Maslak through deep stations carved from the bedrock. Building deep meant long escalator rides through galleries lined with the same rock, a contrast with the shallower M1 stations. Australian business travellers familiar with Melbourne's City Loop will notice the same reliance on tunnel boring and station depth to avoid surface disruption.

Cross the Bosphorus: Marmaray and the Asian side

The symbolic heart of the network is the Marmaray rail tunnel, an immersed tube dropped into a trench dredged across the Bosphorus and opened on 29 October 2013, the ninetieth anniversary of the Republic. Japanese contractors built the thirteen immersed sections in a dry dock near Tuzla and lowered them into a seabed trench running as deep as fifty-five metres below the surface. The journey from Üsküdar to Sirkeci takes just over four minutes.

On the Asian side, the M4 line opened in 2012 between Kadıköy and Ayrılık Çeşmesi, later extended to Sabiha Gökçen Airport in 2022, giving passengers a direct metro link to the second airport. The M5, a fully automated driverless line from Üsküdar to Çekmeköy, opened in 2017 and has since been extended toward Samandıra. These lines have transformed property values in districts that once sat beyond commuting range, much as the Sydney Metro Northwest extension lifted house prices in the Hills District.

Driverless technology and the modern network

Istanbul's metro system now stretches past three hundred kilometres across more than a hundred stations, with several lines operated without drivers from central control rooms. The M7 line, opened in stages from 2020 onward, links Mecidiyeköy with Mahmutbey and uses the same communications-based train control technology found on the Sydney Metro City and Southwest extension. Peak frequencies approach the two-minute mark on the busiest corridors.

A single smart card, the Istanbulkart, allows seamless transfers between metro, tram, ferry, and bus, a feature that Australian commuters in Brisbane or Perth have only begun to enjoy with the rollout of contactless bank-card payments. Station artwork often reflects the neighbourhood above: tiles near the Karaköy exit depict fish markets, while platforms under the Topkapı walls carry geometric patterns drawn from Ottoman tilework.

Future expansion and a global comparison

Planners in the Istanbul Metropolitan Municipality are working toward a target of more than six hundred kilometres of urban rail by the end of the decade, including a third Bosphorus crossing and new lines serving Başakşeir and Beylikdüzü. Compared with Sydney's single metro line and Melbourne's legacy City Loop, Istanbul is closer in scale to Shanghai or Seoul, yet it has achieved this reach in a fraction of the time those cities took.

For Australian policy watchers, the network illustrates how a single metropolitan authority can coordinate tunnel boring and fare collection across two continents. The same governance model is now being studied by Infrastructure Australia as a reference for projects such as the Suburban Rail Loop in Melbourne and a potential second harbour crossing in Sydney.

Practical tips for riders

A practical next step for anyone planning a trip is to plot the Marmaray crossing on a city map before departure, then walk from Sirkeci station to the Eminönü seafront in five minutes and board the next Üsküdar ferry, an itinerary that links the underground railway directly to the older waterway crossings of the Bosphorus.