Istanbul , Turkey ( CNN ) -- As a city that sits astride two continents , Istanbul has always been a strategic gateway between the East and West . But an ambitious railway project is pulling the two continents even closer together with the construction of the world 's deepest submerged tunnel . The 76-kilometer ( 47.2-mile ) Marmaray Project will include the world 's first submerged railway connection between Europe and Asia , ferrying passengers under a 1.4-km ( 0.9-m ) section of the Bosphorus Strait . However , the massive infrastructure overhaul undertaken by Turkey 's Ministry of Transportation has not been without problems . The project started in 2004 and has suffered multiple setbacks due to the region 's rich heritage , as Turkey 's transport minister Binali Yildirim explains . Infographic : Istanbul and the Bosphorus . `` The tunnel is going under a very historical area , [ a ] historical peninsula where the Ottoman Empire settled ... so every piece of soil is examined by experts , archaeologists . '' Yildirim said . At one point during construction , work had to be halted after the discovery of an ancient Byzantine port . `` If [ the archaeologists ] say you can go , we go . If they stay stop , we stop , '' Yildrim said . All of which has added five years onto the original construction deadline . Watch : Navigating the busy Bosphorus . To complicate matters further , the tunnel -- which passes under one of the busiest waterways in the world -- lies in an active earthquake zone . `` There is a big , huge seismic activity risk so we have seismic joints in the tunnels , especially between the immersed tube tunnel and the bore tunnel , '' says deputy project manager , Mehmet Cilingir . The joints between the tunnels are flexible and will protect the structure from seismic movements , Cilingir says . Despite the setbacks , the project is scheduled for completion next year -- a target that will be met , Yildirim says . `` We are very comfortable that the project is going to be complete by the end of next year . 14 million people are just waiting [ for this tunnel to open. '' ] . When it does , the tunnel is expected to ease the congested road and ferry routes above carrying 75,000 passengers per hour in each direction at peak times . Train drivers , like Mustafa Berker , are already getting to grips with the new trains that will operate on the line . `` It will be a great joy for me if I too can add a bit to this big project , '' says Berker , a driver with almost four decades experience . `` I 'm ready for my retirement but if I can see this through , it will be a great pleasure both for me , my children and grandchildren . ''
Marmaray tunnel project in Istanbul will be first railway connection between Europe and Asia . The new tunnel will ease commuter traffic on Istanbul 's waterfront and strait . Tunnel construction has been delayed by discovery of ancient ruins . Seismic is also a problem for contractors who have fitted ` ` flexible joints '' in the tunnel .