A double-tube undersea railway tunnel connecting Europe and Asia, crossing the Bosphorus Strait in Istanbul, Turkey. Trains can travel through the tunnel in less than four minutes.
This tunnel has a 13.6 kilometers long, 1,400 meters run beneath the sea. The maximum depth The ones that pass through this tunnel are the 62 meters.
The Marmaray Tunnel consists of 11 prefabricated double-tube elements, eight are 135 meters long, two are 98 meters long, and the last one is approximately 110 meters long.
The construction of this tunnel faced various challenges, such as strong currents or be able to withstand strong earthquakes, since it is located in an area prone to severe earthquakes, due to its proximity to the North Anatolian Fault. To address this problem, the Marmaray Tunnel is equipped with seismic joints, capable of withstanding earthquakes of more than 7.5 on the Richter scale.
Construction of this marvel of civil engineering began in 2004, and it was inaugurated in October 2013. Construction had to be halted at one point for various reasons; for example, archaeological ruins were discovered during the excavation phase, which forced a temporary halt to the project.
The project cost more than 3.3 billion euros. This tunnel is crossed by more than one million people a day.
