One of the UK’s largest and most technically challenging road projects is set to be completed this summer when the massive Welsh Government funded A465 dualling project is finally finished after 23 years.

The 28-mile (45km) £2bn upgrade to the Heads of the Valleys road was designed to bring prosperity to one of the UK's most deprived areas, linking Monmouthshire to Swansea with a dual carriageway, replacing the previous three lane road.

The work was split into six sections, done from the most to least dangerous for drivers and almost 70 structures - including more than 40 new bridges and a dozen new junctions - have been built.

When completed later this year the final phase alone will have delivered 17.7km of new dual carriageway, 6.1km of sideroads, more than 14km of active travel routes, 38 new culverts, 30 new bridges and 28 retaining walls.

The previous five-mile (8km) section closer to Abergavenny caused controversy, opening three years late and costing £336m - £133m more than initially agreed.

Covering the stretch of road between Gilwern and Brynmawr, the sensitive site ran through the protected steep Clydach Gorge site, which includes hidden caves and geological hazardous terrain.

During the time of the construction works, many in the area dubbed it was ‘the road from hell’ with traders in Gilwern saying business had been decimated as the village had been virtually cut off.

Householders had also suffered with the village of Maesygwartha becoming a rat run for motorists looking for ways of avoiding the length hold ups on the main route.

The road finally opened in 2021- three years late and more than £110m over budget.

The initial budget was for the stretch was £223m but skyrocketed to £336m, partly due to a legal dispute between the Welsh government and contractors Costain.

Speaking on a visit to the A465 project this week, Cabinet Secretary for Transport Ken Skates said: “Fixing our roads is a key priority for us. We’ve spent £1bn fixing and improving our roads since 2021, including more than £250m in the past year.

“This project is an incredibly impressive piece of engineering and a fantastic example of how targeted investment in road infrastructure can deliver on many levels, providing jobs for the local community, improving accessibility, supporting education and skills, alongside delivering environmental benefits.

“It’s been a complex project which has not been without its challenges, and I would like to thank everyone who has played their part in helping us to deliver one of the largest road projects in the UK.”

Commenting, Welsh Conservative Shadow Cabinet Secretary for Transport and Infrastructure, Peter Fox MS said: “This overbudget and well behind schedule project epitomises Labour’s 25 years of failure here in Wales.

“By scrapping many other vital infrastructure projects like the much-needed M4 relief road, the cost of which would have nearly been covered by the Heads of the Valleys price tag, the Welsh public will rightly question whether this gargantuan expense was worth it.

“The anti-motorist Welsh Labour Government needs a change in management. The Welsh Conservatives stand ready to fix Wales.”