Tunnel transformation project making good progress

Catesby Tunnel avatar.jpg
Credit: Beth Walsh Photography

An exciting project to turn a disused Victorian-era railway tunnel into a state-of-the-art vehicle testing facility is moving through the gears as the finishing line grows nearer. 

The £12 million Catesby Aerodynamic Research Facility (CARF) is utilising the disused Catesby Tunnel to create an indoor, fully-controllable vehicle testing centre.

Almost 3km-long and perfectly straight, the tunnel provides a stable underground environment in which vehicles can be driven at high speeds to monitor their aerodynamic performance.

More accurate and efficient than a wind tunnel, the CARF will be the only testing facility of its kind available for hire and is expected to attract interest from across the world, ranging from cycling and motorsport teams to major vehicle manufacturers.

An initial 400-metre stretch of the tunnel has been made operational so far, allowing some testing to begin. It is hoped the rest of the tunnel, which will include facilities for testing wind and simulated weather impact as well as for aerodynamics and emissions, will be completed by May next year.

A new £4 million Research and Innovation Centre is also being built on the site, with the aim of enabling high-performance technology start-ups and early growth businesses to locate next to the testing facility.

Work on this is also progressing well, with the building expected to be made wind and water-tight by the end of next month.

Watch our video to find out more:



Running from Charwelton to Catesby, the Catesby Tunnel was completed in 1897 and operated until 1966, when the Great Central Main Line was closed and abandoned.

The project to bring it back into use is being developed by Brackley-based firm Aero Research Partners (ARP), with work on the initial design phase starting in 2013.

The scheme has attracted a £6.2 million investment from the Government’s Local Growth Fund, secured through the South East Midlands Local Enterprise Partnership (SEMLEP).

Support has also come from Daventry District Council (DDC), which acquired the disused tunnel from the Secretary of State for Transport so it could be leased to ARP.

West Midlands construction and civil engineering firm Stepnell began work on site in January 2018, building a new access road and two-storey main building at the tunnel’s southern entrance. Work to lay a smooth road surface inside the eight-metre-wide tunnel got underway in January this year.

Dr Rob Lewis OBE, managing director of Brackley-based TotalSim, and ARP, said: “As the project nears completion we are eager to start vehicle testing in the tunnel and attracting companies from all over the world to come to Catesby to test. 

“The ultimate success of the facility is down to the public and private partnership between ARP, their investors, SEMLEP, DDC and the Department for Transport. We are very grateful for the support and faith these organisations have shown in the project and we will strive to ensure the project delivers the economic success and source of innovation that we set out to achieve when we started working on this project back in 2013.”

Chief Executive of SEMLEP, Hilary Chipping said: “The South East Midlands area is at the heart of the Oxford to Cambridge Arc of innovation and productivity. We are all clearly facing great challenges at the present time but the automotive research and development that can happen in facilities like this one are key to recovery and future growth.”

Councillor David James, Economic, Regeneration and Employment Portfolio Holder at Daventry District Council, said: “It is fantastic to see the progress that has been made on this unique project to bring a disused rail tunnel back into use in a most innovative way.

“We’re proud as a Council to support the Catesby Aerodynamic Research Facility and the innovation and research centre, which will create new jobs in this high-tech sector and further our District’s reputation as a centre for excellence in the motorsport industry.”


Catesby Tunnel photography commissioned by Stepnell
Credit: Beth Walsh Photography