The construction of the line began in 2006 following the signing of the related contract in May of that year. By March 2009, the tunnels were completed. The rolling stock was delivered in January 2010, and in December of the same year, the first test run of the trains was accomplished. The line's operation rights were transferred from the İETT bus authority to İstanbul Ulaşım company in June 2011. After the line signalization system was completely installed in March 2012, test runs began in June 2012. On 11 September 2012 the M3-line started operating unofficially. The M3-line went into service officially on 14 June 2013. Ziya Gökalp Mahallesi Station is the only underground station bored in situ without removing the ground above, while all other underground stations on the line are built by cut-and-cover method, constructed in a shallow trench and then covered over. The line's tunnels are twin tubes. The line between Kirazlı and MetroKent was constructed by tunnel boring machine while the line between Sanayi Mahallesi and Olimpiyat Parkı was built using the New Austrian Tunnelling method.
Technical features
The M3 line is long, serving 11 stations in total. The operation control center of the M3-line is situated in MetroKent Terminal. The rolling stock and maintenance depots are located in Olimpiyatköy beyond Olimpiyat Parkı Terminal, stretching over an area of. The rolling stock depot is capable of holding 180 cars. The maintenance workshop occupies a covered area of. The rolling stock was delivered by the French company Alstom. The fully air-contioned cars, costing each 1.149 million, feature seats covered with antibacterial textile material. It is possible to pass from one car to another in a train to enable a homogeneous distribution of the passenger crowd. A total of 80 cars, 20 sets of four-car trains, are able to transport up to 70,000 passenger per hour per direction between the operating hours from 6:00 h in the early morning to 0:00 h in the midnight. The ride between the terminals Kirazlı and MetroKent takes 20 minutes. The trains run every five minutes during rush hours.
The stations with long platforms are suitable for even 8-car trains. Mahmutbey Station has a third track available for parking or overnight stay of trains. İkitelli Sanayi Station, which is a junction station, features two platforms and four tracks. Olimpiyat Terminal has two platforms and three tracks. All the stations are painted in different colors, and fitted with escalators and elevators for disabled persons.
Kirazlı Terminal
MetroKent Terminal
Olimpiyat Parkı Terminal
Rolling stock
This line is operated by Alstom trains which are visually similar to the AM5-M2 and AM4-M4 trains also built by Alstom that operate on the Budapest Metro. The main difference is that the Istanbul units are equipped with pantographs for overhead line operation only while the Budapest units are equipped with shoegear for third rail operation only.