Project profile: Tidenham Tunnel

Part cycling commuter route, part tourist attraction, part wildlife haven, the Tidenham Tunnel has been fully restored to its former glory for cyclists and walkers to enjoy as a cool, peaceful interlude along routes around the beautiful Wye Valley.

Location: Wye Valley, Gloucestershire/South Wales

Project managed by: Greenways and Cycleroutes

Tunnel managed by: National Highways on behalf of the Department for Transport

Status: Open to the public

Video: Celebrating Tidenham tunnel’s transformation to Wye Valley Greenway

About the structure

Tidenham Tunnel connects Chepstow and Tintern as part of the Wye Valley Greenway on the border between Wales and England. The tunnel is 1km long and runs 100m below the surface at its deepest point. It opened in 1876 as part of the railway line that ran between Chepstow and Monmouth. It was planned to support the local industrial economy, which centred around iron and copper.

Because goods and passengers had to navigate a long way through the hills and valleys, a new tunnel would shorten this journey. It was hoped that Chepstow would have a chance at competing with the nearby busy industrial ports of Cardiff, Newport and Swansea. By the time the railway was fully running, much of this industry was in decline – but it was rapidly being replaced by a bustling tourist industry as people flocked to the greenery of the Wye Valley.

The line opened in 1876 and closed to passengers in 1959. It operated for goods only – especially taking stone to and from Tintern Quarry – until 1981.

In 2019, after decades of disuse, Sustrans started work on a project to restore the tunnel and turn it into a walking and cycling route. Local charity Greenways and Cycleroutes Ltd successfully applied for planning permission, taking on responsibility for project delivery and maintenance. Their team led negotiations with local people and landowners in its careful design, applying for funding and appointing contractors. A band of local volunteers carried out much of the preliminary site work ahead of the main contractors completing the construction in April 2021; Friends of Wye Valley Greenway still helps to maintain the route.

Because the tunnel is host to a population of bats, which are legally protected and can’t be disturbed when they’re roosting, it's closed for part of the year to protect them. It’s also the reason there is special low-level downlighting, to minimise any disturbance to them and their roosting behaviours.

The path to the north and south of Tidenham Tunnel remains open for the public to use 24 hours a day, 365 days a year. The Wye Valley Greenway website provides information for walkers and cyclists on how to navigate around the tunnel section when it’s closed.

What is the project?

Sustrans took on Tidenham Tunnel with a proposal to integrate it into the popular existing cycling and walking routes around the Wye Valley. We investigated their plans and agreed that it would be a great way to bring the tunnel back into public use. The Department for Transport granted permission for us to lease the structures long-term to Sustrans, who then partnered with Greenways and Cycleroutes.

What stage is it at?

This project is complete. We continue to maintain safety of the tunnel on behalf of the Department for Transport. We fund examinations and maintenance on the tunnel, and provide technical support to Railway Paths Ltd. The tunnel has been open for the public to enjoy since 2021.