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27 August 2017, 11:52
Linking the Lothians and Fife, the new £1.35 billion Queensferry Crossing is the longest three-tower, cable-stayed bridge in the world.
It has taken six years to build the structure, which was commissioned after the Forth road bridge (FRB) was deemed no longer viable as the long-term main crossing of the Firth of Forth.
The construction process has not been without challenges, though, as adverse weather conditions pushed the completion date back several months.
The building work was also hit by tragedy when a worker died last year.
The need for the new bridge became clear after the FRB began to show signs of significant deterioration early in the 21st century, with corrosion resulting in loss of strength in the main cables.
Plans for the new cable-stayed bridge were announced by Scottish ministers in December 2007.
The original estimated cost of the scheme was £3.2 to £4.2 billion but this was reduced to between £1.4 and £1.45 billion after it was decided the existing FRB would become a dedicated public transport corridor carrying buses, pedestrians and cyclists.
Savings announced since then have brought the cost down to £1.35 billion.
The principal contract to build the new bridge and connecting roads was awarded to the Forth Crossing Bridge Constructors (FCBC) consortium in April 2011 while in July that year the contract to upgrade M9 junction 1a at Kirkliston was awarded to a consortium between Irish contractors John Sisk and Roadbridge.
Construction work began in late summer 2011 and the bridge touched down in Fife in August last year when engineers closed a 70cm gap between the north deck and the north approach viaduct, connecting the new bridge to land in the county.
The final segment of the bridge deck was lifted into place in February 2017 and the project moved on to a phase of finishing works.
The 1.7-mile bridge was originally due to open last December but adverse weather delayed the completion date to the end of May and then pushed it back further until the end of August.
More than 10,000 people have been inducted to work on the construction site since 2011, clocking up over 13 million hours of work.
Last spring a construction worker died during the work, the first fatality at the site.
John Cousin, 62, from Northumberland, was reportedly struck by the boom of a crane he was directing on the north tower deck at about midday on Thursday April 28.
Another man also suffered minor injuries in the incident.
The Queensferry Crossing will open to traffic on Wednesday August 30 with an initial 40mph limit to allow work to take place on the FRB to complete its transformation into an active travel corridor.
When the work is complete, public transport will be switched on to the FRB and the Queensferry Crossing will be given motorway status, which is expected to happen in late October or early November.
The name of the bridge was chosen through a public poll in 2013.
The Queensferry Crossing received a third of the 37,000 votes, beating other options such as Caledonia Bridge, Firth of Forth Crossing, Saltire Crossing and St Margaret's Crossing.
After opening to traffic on August 30, the new bridge will be closed from September 1 to September 6 for celebrations before reopening to vehicles from September 7.
Over the weekend of September 2 and 3, 50,000 members of the public will have the chance to walk across it.
After a ballot for the walking experience attracted almost 250,000 entries, an extra community day was added for September 5, giving up to 10,000 more people from local schools and groups on both sides of the Forth the chance to walk across.
The Queen will officially open the new Queensferry Crossing on September 4, exactly 53 years to the day from when she opened the FRB.
Speaking earlier this month, First Minister Nicola Sturgeon said: ''The Queensferry Crossing is a symbol of a confident, forward-looking Scotland and - as well as providing a vital transport connection for many years to come - it is a truly iconic structure and a feat of modern engineering.''
The Queensferry Crossing in numbers:
:: 1.7 miles across - making it the longest three-tower, cable-stayed bridge in the world.
:: 24 million vehicles are expected to use the crossing each year, easing the strain on the Forth road bridge.
:: £1.45 billion cost of the project, down from the original estimate of £3.2 to £4.2 billion.
:: 35,000 tonnes of steel used during construction, 7,000 tonnes alone for the north and south viaducts.
:: 23,000 miles of cables supporting the bridge, almost enough to wrap around the world.
:: 150,000 tonnes of concrete poured over the course of the project, nearly the same amount used for the entire London Olympic Park and athletes village.
:: 210m tall, making it the tallest structure in Scotland and the highest bridge towers in the UK.
:: 10 million man hours involved in the construction.
:: 122 sections make up the bridge deck, each one weighing up to 750 tonnes.
:: 65 options were considered before the cable-stayed bridge design of the Queensferry Crossing was selected.