Final Istanbul M11 metro link opens to complete 69 km line

The final section of Istanbul’s M11 metro line has opened between Arnavutköy and Halkalı, completing a 69 kilometre high speed corridor that now links the western suburbs, the new Istanbul Airport and the central business districts in a single continuous route.

A new backbone for airport and cross-city travel

With the launch of the Arnavutköy–Halkalı section in late June 2026, the M11 Gayrettepe–Istanbul Airport–Halkalı line is now operating as one continuous route across the European side of Istanbul. The opening closes the last major gap in a project whose first stage entered service between Istanbul Airport and Kağıthane in January 2023, before being extended to the inner-city hub of Gayrettepe in early 2024.

Publicly available information describes the completed M11 as roughly 69 kilometres long, making it one of the world’s longest dedicated airport metro corridors and among the longest single metro lines in Europe. The route combines express-style running over long outer-city stretches with frequent urban stops closer to the centre, designed to balance airport access with daily commuting needs for growing residential districts north and west of the city.

The full line now connects Halkalı in the west to Gayrettepe in the inner business district via Istanbul Airport and Arnavutköy, with intermediate stations serving fast-developing areas such as Kayaşehir and the Olympic precinct. Travel time figures shared in Turkish media indicate that journeys between Halkalı and Gayrettepe are expected to take under an hour, while the end-to-end time between Halkalı and Istanbul Airport is projected at about half an hour.

New connections for fast-growing western districts

The completion of the M11 has immediate implications for residents of Istanbul’s western suburbs, many of whom have relied on road-based buses and private vehicles to reach both the city centre and the new airport. The newly opened section links Arnavutköy and neighbouring districts directly to the rail network, offering an alternative to congested highways and often unpredictable road travel times.

Halkalı itself is a significant rail hub on Istanbul’s European side, already served by suburban, intercity and high-speed services, along with the Marmaray trans-Bosphorus tunnel. By extending the M11 into this node, planners have effectively stitched the airport corridor into the city’s wider regional rail system, allowing passengers from across the Marmaray axis to reach Istanbul Airport with a single connection.

Reports on the new section highlight multiple interchange points with existing and planned metro lines. These include transfers to the M3 line at Kayaşehir, the M9 at Olimpiyat and, in future, the M7 at Halkalı Stadı. This mesh of connections is expected to redistribute passenger flows across the network, easing pressure on road-based airport shuttles and traditional arterial routes into the centre.

Network integration at Gayrettepe and key interchanges

At the inner-city end of the line, Gayrettepe has emerged as a deep-level interchange between the M11 and the long-established M2 metro, which runs north–south through key business and commercial districts. Passengers arriving from the airport can transfer here toward Taksim, Levent and Yenikapı, while those starting in the historic peninsula or along the Golden Horn can reach the airport with a single cross-platform change via M2 and M11.

Since the Gayrettepe extension began operation in January 2024, the station has been handling rising volumes of airport-bound travellers alongside office commuters. Observers note that the opening of the Halkalı section is likely to further increase footfall, transforming Gayrettepe into one of Istanbul’s most heavily used interchanges as the full 69 kilometre corridor settles into daily operation.

Additional interchange opportunities along the route broaden its role beyond airport access. At Arnavutköy and intermediate stations, M11 links with bus networks that serve surrounding neighbourhoods, while future projects referenced in planning documents suggest potential for further integration with new metro and suburban lines. For travellers, this means that the M11 now operates both as a fast airport link and as a backbone for a wider, gradually densifying rail grid on the European side.

Travel times, fares and early passenger experience

Published coverage around the opening indicates that travel times along the full line are a central part of the project’s appeal. Indicative journey figures suggest that Halkalı to Istanbul Airport can be covered in around 30 minutes, compared with significantly longer and less predictable trips by road during peak congestion. Gayrettepe to the airport is reported at roughly 30 minutes, giving many central city passengers a reliable sub-one-hour door-to-door journey when transfers are included.

In the initial weeks following launch, Turkish media reports have highlighted promotional fare arrangements for the new section, including temporary free or reduced-cost travel windows. These measures are framed as a way to familiarise residents with the new rail option and to encourage a modal shift away from private cars and airport coach services. Regular tariff integration with Istanbul’s existing smartcard-based fare system is expected to keep the route competitive once introductory offers expire.

Early accounts from passengers shared on local forums and social media describe trains as modern and fast, with on-board information systems tailored to airport users and luggage-friendly interiors. Some posts also point to long walking distances at certain interchanges, particularly in deep stations such as Gayrettepe, underscoring the trade-off between high-speed tunnelling and surface accessibility in densely built urban corridors.

Strategic significance for Istanbul’s long-term transport plan

The full commissioning of the M11 comes as Istanbul continues an ambitious expansion of its metro and rail network, part of long-term plans to increase the share of public transport in daily trips and reduce pressure on arterial roads. Official planning documents have highlighted the airport corridor as a priority investment, given both Istanbul Airport’s role as an international hub and the rapid urbanisation of surrounding districts.

Observers note that, by completing the M11 to Halkalı, Istanbul has created a continuous high-capacity rail spine that links the city’s traditional core with its primary air gateway and major suburban growth areas. Over time, the line is expected to support transit-oriented development around outlying stations, potentially reshaping land use patterns and reducing car dependency in new residential zones.

Transit commentators also point out that, despite its length, the M11 remains only one element of a much larger rail puzzle. Future projects on both the European and Asian sides, as well as further cross-Bosphorus links, are likely to determine how fully the benefits of the new airport corridor are realised. For now, the completion of the final section to Halkalı marks a substantial milestone, redefining how residents and visitors move between Istanbul’s western neighbourhoods, its central districts and one of the world’s busiest airports.