The Capital Express was one of the six daily intercity trains operating between Istanbul and Ankara on the Istanbul-Ankara railway before the Yüksek Hızlı Tren high-speed train service replaced all intercity trains on the line. The Capital Express was the fastest of the six trains, making limited stops only in large cities. The train would complete its journey in just over four hours and in the Eskişehir Province, trains would reach conventional speeds of 150 km/h (93 mph), which still hold the record for fastest conventional train service in Turkey. When the high-speed rail service was opened between Ankara and Eskişehir on 13 March 2009, the Capital Express, along with the other five intercity trains, were cut back between Istanbul and Eskişehir. During this period two more daily intercity trains were added, the Sakarya Express and Eskişehir Express, increasing daily intercity service to eight trains.

Bostancı railway station is a railway station in Kadıköy, Istanbul and is the easternmost station in the district. Located along Bağdat Avenue in the Bostancı neighborhood of Kadıköy, it was a station on the Haydarpaşa suburban between 1951 and 2013, when the railway between Haydarpaşa and Pendik was closed. On 12 March 2019 the station reopened to Marmaray commuter rail service. Prior to 2012, the station was also serviced by many intercity trains to Ankara and Anatolia as well as frequent regional train service to Adapazarı. Bostancı station is 8.64 km (5.37 mi) away from Haydarpaşa Terminal.