Cameras have been allowed to film inside the top-secret Government Communications Headquarters (GCHQ) for the first time. Supervised filming was allowed in the organization’s 24-hour spy center located in Cheltenham, an incredibly rare occurrence, with signs are put up around the building warning staff against having sensitive conversations in the visitors’ vicinity.
The organisation is responsible for signals intelligence (SIGINT) – the gathering of intercepted communications and electronic signals. The data gathered by golf ball-shaped monitoring stations at some RAF airbases is sent to GCHQ where it is decrypted and analyzed.
At first glance, GCHQ looks like a typical office complex, but the building itself is an imposing doughnut-shape ringed by razor wire-topped fences. The main circular internal corridor is known as “the street.” Offices close to the inner circle look out onto the circular garden in the center of the structure. The enclosed outdoor space is deliberate. It’s thought the design limits how much sound from conversations can carry upwards towards any spy satellites above.
Inside the doughnut, there’s a small museum housing the first Enigma decoding machine, which cracked German codes during the Second World War. Also on display are the notes on JRR Tolkien’s application to join the Bletchley Park codebreakers.
GCHQ was established after the First World War and its very existence was not acknowledged until the 1980s. The Doughnut houses 5,500 employees, making it Cheltenham’s biggest employer.