More than a century ago, it was an Ottoman sultan's distant dream. Now, an underground rail link between Europe and Asia in Turkey's metropolis Istanbul is becoming reality, connecting “London with Beijing" in the words of the prime minister, Recep Tayyip Erdogan.

Turkish leaders are scheduled to gather in Istanbul on Tuesday, the 90th anniversary of the republic, to open the Marmaray rail link that can carry up to 75,000 passengers and thousands of tonnes of freight an hour through twin concrete tunnels beneath the Sea of Marmara.

"We are connecting London to Beijing," Mr Erdogan said of the project this month. "It is a dream of 150 years." The government says the 1.4-kilometre section of immersed tube tunnel is the deepest of its kind in the world at 55 metres.

The immediate aim of the state project, begun in 2004 and built by a Turkish-Japanese consortium at a cost of an estimated US$4.7 billion (Dh17.3bn), is to reduce road congestion in Istanbul, a city with a booming economy, 15 million people and 3 million cars.

About 140 million vehicles cross Istanbul's existing two motorway bridges across the Bosphorus Strait every year, almost three times the bridges' original capacity. A third bridge that is being built across the Strait north of the city is to be completed in 2015.

Marmaray is designed to carry more than a million rail commuters between Europe and Asia through its earthquake-proofed tunnels every day.

Today, Mr Erdogan, the president, Abdullah Gul and other officials will inaugurate an initial 13.6km stretch of an underground connection between the districts of Kazlicesme on the European side and Ayrilikcesme on the Asian shore.

After above-ground extensions of 64km are completed by 2016, the line will be roughly 77 km long and connect Gebze in Istanbul's Asian south-east with Halkali in the European west, with an estimated travel time of one hour and 45 minutes. The same trip typically takes twice as long with the existing public-transport system on Istanbul's congested roads.

Marmaray is to be integrated with a growing network of Metro lines on both sides of Istanbul that is to reach close to 800km by 2030, from the current 124km.

Istanbul's municipality has been trumpeting the extension plans with the slogan “Metro everywhere, Metro going everywhere" on bridges and flyovers all over the city. It is also planning a cable-car link across the Bosphorus, to be completed in 2015.

The question of how best to link the two parts of Istanbul has vexed authorities in the city for centuries.

Transport minister Binali Yildirim said in a recent speech that the Ottoman ruler Sultan Abdulmecid first proposed the idea of building a transportation tunnel under the Sea of Marmara in the 1860s.

The sultan reportedly asked a French engineer to work out the plans for such a tunnel, but the project came to nothing.

Mr Yildirim said Marmaray could not only be used to carry passengers, but to transport freight as well, reflecting the Turkey's hope that trade by rail between Europe and Asia countries as far as China will get a boost.

“This project of 150 years is a part of an iron Silk Road," the minister said, referring to the fabled trade route between Europe and Asia.

Suleyman Karaman, head of Turkey's state rail company TCDD, said this year that the Marmaray project opened up new possibilities in international passenger and freight transportation by rail.

He said a new rail connection linking Kars in eastern Turkey with Georgia and Azerbaijan, to be completed next year, would allow more trade through Central Asia.

“The aim is to carry an initial 6.5 million tonnes of freight a year with the Kars-Tiflis-Baku project," Mr Karaman said. High-speed train links in Anatolia currently under construction would offer “an important transport alternative for the Middle East, Central Asia and East Asia".

The completion of the Marmaray project was delayed by several years after significant archaeological finds interrupted construction. In 2006, digging for the construction of an underground station in Yenikapi, a district on the European shore, unearthed an ancient Byzantine harbour, complete with ships and dice used by sailors.

Source: Thenational.ae