WWII Fan Bay Plotting Room Bunker Opens to Public in Dover

A historic command bunker, long kept secret beneath the white cliffs of Dover, is finally opening its doors to the public. Starting this Friday, visitors can access the Fan Bay plotting room, a vital defensive site from the Second World War that was buried four metres underground. While many people search for Dover second world war history, this newly accessible site offers a unique look at the technology used to protect the British coast during the conflict.

Commissioned by Winston Churchill, the bunker served as the "brain" for a gun battery designed to target enemy ships in the English Channel. Following a 1940 memo in which Churchill demanded better defences for the straits, the site was constructed with remarkable speed, with the plotting room completed just 64 days after the guns were installed. The facility housed an advanced electromechanical computer, known as a fire direction table, which calculated the positions of moving vessels to coordinate artillery fire.

The Fan Bay plotting room housed a pioneering computer-aided targeting system used to defend the English Channel.

Jon Stewart, who led the National Trust’s excavation project, rediscovered the site in 2017. The bunker had been mothballed in 1957 and remained classified until 1981. Stewart described the discovery as a significant moment for archaeology, noting that the team found the room largely as it was left, complete with period newspapers, shoes, and graffiti left by the workers who installed the cables. The electromechanical computer itself was destroyed in 1957 to prevent it from falling into enemy hands.

Preserving History

Rather than attempting to reconstruct the past, the National Trust has conserved the site to reflect its state at the time of discovery. Visitors can enter the bunker through a hatch in a field, following the same routes once used by the personnel stationed there. The site provides a rare, authentic glimpse into the clandestine operations that occurred on the frontlines of the British coast. Stewart is currently seeking information from families of those who served at the facility, as official records regarding the operators remain sparse.

Why it matters

The opening of the Fan Bay plotting room provides a tangible link to a critical period of military history that was previously hidden from public view. By preserving the site in its original state, the project allows for a deeper understanding of the technological and human efforts required to defend the coast during the war, offering a new perspective on the history of the white cliffs of Dover.