User:Central Data Bank/Northern Istanbul high-speed railway

The Northern Istanbul high-speed railway (Kuzey Istanbul yüksek hızlı demiryolu), also known as the Northern Istanbul railway bypass (Kuzey Istanbul demiryolu geçişi) or the simply the 3rd Bridge Railway (3. Köprü Demiryolu), is a 63 km long high-speed rail line under construction in Turkey. The railway will begin at Halkalı station in Küçükçekmece, Istanbul and end near Gebze station in Gebze, Kocaeli. The line will run through northern Istanbul Province, keeping north of the city of Istanbul, and will connect to the Istanbul New Airport and Sabiha Gökçen Airport. The railway will also become the second railway to cross the Bosporus strait, after the Marmaray Tunnel, crossing the waterway via the Yavuz Sultan Selim Bridge.

Overview
The railway is planned as a bypass route of the city of Istanbul, similar to the Northern Marmara Motorway. The necessity for this bypass comes from the lack of further railway development in the city, outside of its southern shore. With the Marmaray commuter rail system expected to begin in late 2018, the existing two railways, connected by the Marmaray Tunnel, will become quite busy limiting headways for intercity passenger trains and especially freight trains. The Northern Istanbul high-speed railway will provide an alternate route through the Istanbul Province.