A new attraction on the White Cliffs of Dover is under development, with the National Trust set to open up a network of wartime underground tunnels to the public.

Due to open in May, the tunnels at Fan Bay were used for detecting the approach of enemy aircraft during World War Two.

Speaking at a public Dover Society meeting, National Trust visitor experience manager for the region Jon Barker said that 70 volunteers are now being sought to act as tunnel guides for the attraction.

Sound (or acoustic) mirrors were one of the first early warning detection systems invented to give advanced notice of an approaching enemy aircraft. These worked by focusing the sound from the plane’s engine so it could be heard before it was visible. One of the main features of the attraction will be the mirrors, which Barker said were in perfect condition despite being buried in the tunnels for years.

The National Trust is currently recording the interior of the tunnels before starting work on making essential repairs. The tunnels will remain in their current condition as much as is possible, to reflect how they would have looked when they were abandoned.