[7] A crossing route over the Forth had existed at the site since the eleventh century, when the queen of Scotland, Margaret, founded a free ferry to take pilgrims north to St Andrews.

Proposals for an additional road crossing at Queensferry were drawn up in the early 1990s, as part of the "Setting Forth" consultation document prepared by the Scottish Office.

[9] The plans met stiff opposition from environmentalists and from the City of Edinburgh Council on the grounds of increased traffic.

[12] Between 2003 and 2005, an inspection programme found that the main suspension cables had suffered an estimated 8–10% loss of strength as a result of corrosion.

Projections highlighted the likelihood of an accelerating loss of strength, with traffic restrictions to limit loading required in 2014 in the worst-case scenario.

[13] In 2006-2007 Transport Scotland carried out a study to examine the options and in December 2007, the decision was made to proceed with a replacement bridge.

[15] Scottish Transport Minister Nicol Stephen commissioned a new study, which priced a second Forth Road Bridge at £300 million, in 2003.

[17] In 2007, the Forth Replacement Crossing Study was commissioned by Transport Scotland to examine various options for new bridges or tunnels across the Forth.

[25] A joint venture between consultancies Arup and Jacobs was appointed as project manager, and in February 2008 environmental and technical studies were begun, continuing through 2009.

[27] An environmental statement was published in November 2009,[28] coinciding with the introduction of the Forth Crossing Bill into the Scottish Parliament by John Swinney.

A majority of MSPs voted in favour of the new legislation on 16 December 2010,[29] and the Forth Crossing Act received royal assent in January 2011.

[31] Although Transport Scotland received 39 expressions of interest, concerns over the risks associated with the fixed-price contract resulted in only two consortia of large construction companies bidding.

[33][34] Bids for the main contract, priced at between £900 million and £1.2 billion, and including design and construction of the bridge and approach roads,[33] were submitted in January 2011.

The contract to implement the Intelligent Transport System (ITS) traffic management system in Fife was awarded to John Graham (Dromore) Ltd, with a tender of £12.9 million, while the upgrade of M9 Junction 1a was awarded to a joint venture between John Sisk and Roadbridge, with a tender of £25.6 million.

[47] An additional delay was announced in March 2017 as a result of high winds, making work on the structure difficult and unsafe for workers.

[59] The M90 was extended west from the existing bridge access at Ferry Muir, wrapping around South Queensferry to the southern landfall of the new crossing.

The ITS is an active traffic management, enabling variable speed restrictions and lane closures to be displayed on overhead gantries.

[64] On the northern side two post-built structures and their surrounding pits were found, and dated to the mid to late Mesolithic period.

The structure, based around an oval pit approximately 7 metres (23 ft) in length, contained the remains of a hearth, stone tools, and bone from a variety of animals.

Radiocarbon analysis gave a date of c.8300, about 1000 years older than the northern site, making it the earliest known dwelling in Scotland.