The decision also updated the price tag of the tunnel in light of both the new project timeframe and changing economic conditions. Earnings from 2006 will be recalculated according to current prices -- when the rise in inflation alone is taken into account, this means a 50 percent increase in the $1 million cost of Marmaray tunnel and station construction. In other words, the archaeological delays will cost four-and-a-half years and at least $500 million.
But knowledge of the history of İstanbul has also been changed forever by this project, with the delays being fruitful in terms of archaeological discovery. Artifacts found in the undersea excavations have revealed that the history of İstanbul stretches back not 2,700 years as was previously believed but 8,500 years. Digs at Yenikapı as part of the Marmaray project have resulted in the discovery of 33 ships from the Theodosius port, the oldest segment of wall from the Byzantine period, a Byzantine church and thousands of artifacts. In the layer beneath the Theodosius port, four human skeletons were found, thought to belong to around 6500 B.C., in addition to wooden defensive weapons, wooden furniture and canoe oars.
The foundations were laid for the Marmaray line by Prime Minister Recep Tayyip Erdoğan on May 9, 2004, and construction is being carried out by the General Directorate of Railroads, Ports and Airports Construction (DLH), Japanese contractor Taisei Corporation, Turkish firm Gama-Nurol and the Avrasya Consultancy firm. The project encompasses 13.6 kilometers of tubing, 1.4 kilometers of which is underwater. The 36-station line will provide travel between the European and Asian sides of İstanbul in just two minutes and with extreme connectivity allow seamless transfers to other forms of transportation throughout the city, including lines that connect to the airports.