The Asian Infrastructure Investment Bank (AIIB) and the Republic of Türkiye have signed the first phase of a financing package amounting in total to up to USD1.5 billion for the Istanbul North Rail Crossing Project (INRAIL), a major rail investment designed to strengthen cross-Bosphorus connectivity, according to a press release issued on July 21, 2026. The project reinforces Türkiye’s role as a strategic transport gateway between Asia and Europe. It will support the construction of a new high-capacity rail corridor linking Istanbul’s European and Asian sides via the Yavuz Sultan Selim Bridge.
The investment directly tackles one of Türkiye’s most critical intercontinental rail bottlenecks by expanding cross-Istanbul rail capacity. It aims to improve the efficiency of freight and passenger transport while accelerating a shift from road to rail. With a total project cost of approximately USD8.27 billion, INRAIL ranks among AIIB’s largest transport investments in Türkiye. AIIB is co-financing the project alongside the World Bank, the Asian Development Bank, the Islamic Development Bank, the European Bank for Reconstruction and Development and the OPEC Fund for International Development.
Once completed, the project will deliver approximately 127 kilometers of double-track, electrified, and fully signalized railway connecting Çayırova on Istanbul’s Asian side with Çatalca on the European side. The line will support passenger services at speeds of up to 160 kilometers per hour and freight services at 80–120 kilometers per hour. It will also create seamless connectivity between Istanbul Airport, Sabiha Gökçen Airport, and Türkiye’s high-speed rail network. Rail freight travel time between Çayırova and Çatalca is expected to fall from around 13 hours to 3.6 hours. Passenger travel between Istanbul Airport and Sabiha Gökçen Airport by public transport is expected to be nearly halved, from around 120 minutes to 65 minutes.
“The Istanbul North Rail Crossing Project represents a strategic investment in Türkiye’s transport future and one of AIIB’s most significant connectivity operations to date,” said Konstantin Limitovskiy, Chief Investment Officer, Region 2, AIIB.
He added that removing a longstanding structural bottleneck demonstrates how sustainable, technology-enabled and connected infrastructure can generate lasting economic opportunities. Kerem Dönmez, Director General of Foreign Economic Relations at the Ministry of Treasury and Finance, described INRAIL as one of Türkiye’s most strategic transport investments. He noted the financing reflects the confidence of international development partners in Türkiye’s economic fundamentals and project implementation capacity. He also highlighted the project’s role in strengthening the Middle Corridor’s competitiveness.
By complementing the existing Marmaray corridor and enabling the separation of freight and passenger operations, the project will strengthen the resilience and efficiency of Türkiye’s rail network. INRAIL is projected to reduce greenhouse gas emissions by approximately 16 million tonnes of carbon dioxide equivalent over its operating period. AIIB’s financing will contribute primarily to climate mitigation, with additional adaptation benefits through enhanced infrastructure resilience. The investment supports Türkiye’s transition to a lower-carbon and more resilient transport system. It stands as a cornerstone of a broad-based multilateral development bank partnership.
