Istanbul (AFP) - Turkish President Recep Tayyip Erdogan went for an inaugural spin on Saturday in Istanbul's latest mega-project: the first-ever road tunnel linking the city's European and Asian sides under the Bosphorus Strait.
Images released by the presidency showed Erdogan behind the wheel of a black car, with Prime Minister Binali Yildirim and Transport Minister Ahmet Arslan as his passengers as they made the first journey through the tunnel.
Construction of the five-kilometre (3.1-mile) tunnel, which opens to the public on December 20, began in February 2011. It has two levels which will be open to traffic.
Travel across the two sides of Istanbul will be cut down to 15 minutes from 100 minutes, the presidency said on its website. It will cost $4 (3.50 euros) plus taxes to use the Avrasya (Eurasia) tunnel, Arslan said.
The tunnel will provide "significant relief" for the notorious traffic in Turkey's economic hub, Yildirim said, according to his website.
It is the latest in a series of key infrastructure projects in Istanbul including the city's third airport, due to open in the second quarter of 2018.
In its first phase, the airport will have an annual capacity of 90 million passengers but will later have be able to handle 150 million travellers.
This would mean the $29 billion airport would overtake the total combined traffic of 140 million people who pass through Charles de Gaulle in Paris and London Heathrow, making it Europe's largest airport.
In August, Erdogan inaugurated Istanbul's third bridge -- one of the longest suspension bridges in the world -- over the Bosphorus, just over a month after a rogue military faction tried to oust him from power in the July 15 failed coup.
Speaking after the drive, Erdogan, a former Istanbul mayor, said 156 million journeys had been made via the Marmaray underground railway tunnel which has linked the two sides of the Bosphorus since October 2013.
He described that project as a "dream come true", saying it had significantly improved public transport for Istanbul's 15 million residents by making it quicker to get across the two sides.
Dubbed the "project of the century", the Marmaray was the first giant project initiated by the president who was then prime minister.
"Of course, we also knew this: without a dream, nothing real can be achieved. This is work that can be done and was achieved by those with faith and perseverence," Erdogan said, according to the presidency's website.