Köseköy railway station  Köseköy railway station () is a railway station in Kartepe, Turkey, in the İzmit metropolitan area. TCDD Taşımacılık operates four daily regional trains between Istanbul and Adapazarı that stop at the station. The station was originally built in 1975 by the Turkish State Railways, when the Istanbul-Ankara railway was realigned to bypass İzmit's city center. The "Köseköy Logistics Center" is located adjacent to the station and is an important freight yard on the railway. Köseköy station was closed down on 1 February 2012 due to construction of the Ankara-Istanbul high-speed railway. The station was reopened in 2018.