The famous Glasgow landmark was opened on June 26, 1970 by the Queen Mother following just over three years of construction at a cost of £11 million, which is the equivalent of £180m today.

The Kingston Bridge is 270m long, over 40m wide and crosses the River Clyde at a maximum height of almost 20m.

Cabinet secretary for transport, infrastructure and connectivity, Michael Matheson, said: “The Kingston Bridge has become an iconic landmark in Glasgow over the half century it’s been in operation.

“The crossing played its part in taking a significant amount of traffic off the city centre streets and paved the way for the pedestrianisation of Sauchiehall Street, Buchanan Street and Argyle Street. There is no doubt it continues to play a vital role, carrying around 155,000 vehicles a day.

“The work that’s been carried out to ensure it continues to do this job in the future has also won civil engineering awards, so applying to have the Kingston Bridge listed seems a fitting way to mark its impact over the past 50 years.”

The Glasgow Motorway Archive, in collaboration with Transport Scotland, is also releasing a number of previously unseen photos of the Kingston Bridge from the late 1960s and early 1970s.

Stuart Baird from the Glasgow Motorway Archive said: “The Kingston Bridge was recognised as one of the most ambitious infrastructure projects ever undertaken in Scotland at the time, and it’s had a huge impact in shaping the city over the last five decades.

“Listing the bridge doesn’t simply acknowledge its unique engineering and architectural features, it also recognises the work of the people that designed, built and maintained it over its first half-century of service.

“The Glasgow Motorway Archive’s volunteers have really enjoyed this project, and look forward to sharing some brand new material on our social media channels, but we’re always keen to speak to people who worked on the bridge or other large roads projects across Scotland.”

Transport Scotland has applied to Historic Environment Scotland to have the Kingston Bridge listed as a structure of historic and architectural interest.

Elizabeth McCrone, head of designations at Historic Environment Scotland, said: “The Kingston Bridge is a key part of Scotland’s first motorway and is one of the busiest road bridges in Europe.

“Scotland has a strong heritage of engineering achievements and the Kingston Bridge was designed by W. A. Fairhurst & Partners, one of the leading civil engineering firms of the period.

“We’d love to hear what the people of Scotland think about the proposal to recognise the Kingston Bridge as a listed structure and you can do this by going to our website and giving your views here.”