A63 Castle Street underpass in Hull to open on 23 March

The long-awaited A63 Castle Street underpass in Hull city centre will open to traffic on Monday 23 March, National Highways has confirmed.

The underpass forms a key part of the £355 million Castle Street improvement scheme, which began construction in 2020 and aims to improve traffic flow and connectivity between Hull city centre and the port.

The project has involved lowering a section of the busy A63 into an underpass, allowing Ferensway and Commercial Road to connect at street level above the route.

Complex engineering project

Senior project manager Fran Oliver described the construction as one of the most technically challenging road schemes in the country.

“Construction of the A63 underpass has been one of the most complex engineering challenges in the UK,” she said.

Oliver added that the scheme required specialist engineering expertise and extensive technical work.

“It has been a fantastically large project,” she said, noting that engineers had to carry out complex design calculations throughout the build.

Delay due to ground conditions

The underpass was originally scheduled to open in April 2025, but the completion date was pushed back by around a year due to extremely challenging ground conditions encountered during construction.

Despite the delay, National Highways said the project has now reached a major milestone, with the new road layout expected to be fully operational by the morning of 23 March.

Discoveries during excavation

Archaeological investigations carried out alongside the construction works uncovered several significant historical finds, including the remains of a victim from one of Hull’s worst dockland disasters, as well as an 18th-century jail, a suspected Second World War bomb site, and evidence of a medieval settlement.

Boost for connectivity and local economy

National Highways said the scheme will improve links between the city centre, the port and nearby leisure destinations, helping to support Hull’s economy and tourism.

Hull City Council leader Mike Ross welcomed confirmation of the opening date.

“Residents across the city will breathe a sigh of relief with the news that the underpass is to open in the coming weeks,” he said.

Ross acknowledged the disruption the project has caused during construction but said the completion of the scheme would represent a significant step forward for the city.

“It is clear the scheme has caused considerable disruption for many – both residents and businesses alike,” he said.

“The completion of this aspect of the A63 project is just another reason why 2026 is a landmark year of positive change for Hull.”

Oliver added that the project team appreciates the patience of residents and businesses during the works.

“This eagerly anticipated new road layout will increase connectivity between the centre of the city and the port and other leisure activities,” she said.

“We appreciate everyone’s patience and understanding as we’ve worked to get to this significant milestone.”