The main contractor has now completed the erection of all three towers and the installation of a 1.1km long stretch of steel cable across the River Thames.

Matt Randall, Project Director for Mace, said: “Now the cable has been tensioned to the correct height, the next step will be to commence the testing of the whole system.”

The 34 cabins will undergo a rigorous testing process which will involve hours of running the cables and cabins across the river before it is due to open for passenger service this summer.

Randall said: “The pull of the cable across the Thames has been a highly complex and intricate part of the construction of this landmark project.

“We used boats to make the initial rope connection during the short night-time window when the tide was at its lowest, working with the Port of London Authority to keep the river way clear, and this was eventually replaced with the cable itself.

Main construction works on the UK’s first urban cable car have been taking place either side of the river since July 2011.

The three main towers will allow 34 cabins to cross the river at heights of up to 90 metres between the two terminals, Emirates Greenwich Peninsula and Emirates Royal Docks.

The three towers were manufactured in Bolton by Watson Steel and have been erected in sections via crane.

At around 90m tall, the South Tower is the only tower to have been built in the River Thames next to the O2.

The cabling is made of twisted steel comprised of nearly 300 separate strands of steel and 50mm thick.

It was pulled into place and tensioned using a 12-tonne winch located on the platform of the South Terminal (Emirates Greenwich Peninsula).