Bosphorus Bridge (1973) Istanbul, Turkey
The Bosphorus Bridge was built in 1973 to span the Bosphorus Strait in Istanbul, Turkey. It is also known as the First Bosphorus Bridge since the construction in the 1980s of the Fatih Sultan Mehmet Bridge just 5 kilometres upstream. It is a steel gravity anchored suspension bridge, 1,560m (5,118 ft) in length and 33.5m (110 ft) wide. The main span is 1,074m (3,524 ft) long between two 165m (541 ft) towers and the deck stands 64m (210 ft) above water. There are nine side spans ranging in length from 40m (131 ft) to 64m (210 ft).
Bridging the Bosphorus to link Europe and Asia was considered for many centuries and there are records of a pontoon bridge constructed BC to enables armies to cross. In 1900 the Bosphorus Railroad Company proposed a permanent road and rail bridge but it was not until 1957 that the Turkish Prime Minister gave the go-ahead to finally construct a bridge.
It took another 11 years before a contract was signed and a bridge was then designed by British Civil Engineers, Sir Gilbert Roberts and William Brown whose notable other projects included the Humber, Severn and Forth Road Bridges. Construction began in 1970 and was completed three and a half years later in October 1973.
The bridge carries a total of eight lanes (two of which are reserved as emergency lanes). On weekdays four of the six lanes are dedicated to rush hour traffic westward in the mornings and eastward in the evenings. The bridge is a toll bridge but a toll is only payable for traffic crossing from Europe to the Asian side. Approximately, 180,000 vehicles cross the bridge daily but commercial vehicles are not allowed. Pedestrians were permitted to use the bridge when it was first opened but this is no longer possible.