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Catesby Tunnel is set to become a worldwide benchmark for vehicle testing, capable of providing accurate and affordable full scale aerodynamic and performance data. The facilities are now open to the public, since early November 2021.


Catesby Tunnel began construction as a Victorian railway tunnel in February 1895 and was completed in just over two years in May 1897. The railway line was part of the Great Central’s ‘London Extension’ with the first train running through in July 1898. The railway tunnel was in service for 68 years until its operational retirement in September 1966. The underground nature of the construction was a result of Catesby Estate owner, Henry Attenborough, objecting to unsightly trains passing through the landscape. Approximately 30 million bricks were required to construct the perfectly straight 2.7km long tunnel.


Catesby Tunnel is currently undergoing a multi-million pound transformation to convert the disused railway tunnel into a state-of-the-art vehicle testing facility. The project is being developed by Brackley based Aero Research Partners who initiated the design phase back in  2013. As of 2020, the project has attracted £6.2 million of investment from the Governments’ Local Growth Fund, secured through the South East Midlands Local Enterprise Partnership. A 400m road surface has already been laid out for initial testing. The remaining sections are expected to be completed in early 2021.


Catesby Tunnel is set to become the worldwide benchmark for aerodynamic testing and vehicle development. The facility is expected to attract customers from Europe and the rest of the world. The development will enhance the capabilities of the UK vehicle industry and provide a base for the commercialisation of new technology, innovation and R&D. A science and technology park will be built adjacent to the tunnel that will bring together high tech companies allowing opportunities for collaboration and growth in the South East Midlands.