The incredible £335bn bridge or tunnel that could have linked two UK countries
At first the idea was given an estimated cost of £15bn but it seems that was a huge under-estimate.
An ambitious multi-billion-pound plan made the prospect of a bridge or a tunnel connecting Northern Ireland and Scotland a real possibility.
The idea was suggested as far as the 1890s, but was revived by the Democratic Unionist Party (DUP) in Northern Ireland back in 2015.
Former Prime Minister Boris Johnson was arguably the most vocal backer of the idea in recent years.
The bridge was initially pitched with an estimated cost of between £15billion and £20billion to build.
Two routes were proposed. One linked Portpatrick to Larne while the other would have seen the bridge span from Campbeltown to the Antrim coast.
READ MORE: UK’s cheapest town laid bare where homes only cost £69k - full list
In March 2020, it was reported that the plan could be changed to make it a tunnel connecting Northern Ireland and Scotland instead.
Then Scottish Secretary Alister Jack said he was "very keen on it now, but it’s not a bridge that I’m keen on, it’s a tunnel".
However, Mr Johnson had to ditch the plan publicly in September 2021.
After a visit to the US, he told reporters he was downgrading the plan to an "ambition".
Two months later, the plan was ruled out after a study revealed the costs and engineering challenges involved.
Transport expert Sir Peter Hendy advised the government at the time it was not viable.
A Government source told the Telegraph that Sir Peter had found that the project "would be technically very challenging at the moment".
Don't miss...
'Amazing' part of the UK applauded by tourists for 'next level' friendliness [LATEST]
'Fake pub' and 'chip shop' in eerie 'UK Chernobyl' where flats go for just £7k [LATEST]
UK’s cheapest town laid bare where homes only cost £69k - full list [LATEST]
The source added: "That's not to say it won't become viable at some point in the future, but at the moment it would be very, very difficult and expensive."
It was later revealed that the bridge would actually cost an estimated £335billion while a tunnel would have set the country back £209billion.
In January 2022, it was revealed that Sir Peter's research had cost the taxpayer £900,000.
A Department for Transport spokesperson said at the time: "Communities across the United Kingdom want to see better connections between Scotland, Wales, Northern Ireland and England, which is why we have explored all options and have sought to work with the devolved governments to deliver that.
"The purpose of the Union Connectivity Review was to examine, in detail, all aspects of transport connectivity between the nations to boost and deliver further opportunities for people, families and communities.
"As part of this detailed review, we consulted with the best engineers and technical consultants and undertook extensive social and geographical research to carry out a comprehensive study.
"This has informed our approach to rail, road and air, including making travel cheaper for all parts of the UK by reducing Air Passenger Duty by 50 percent for domestic flights."
