Discover the remarkable world of codebreaking, ciphers and secret communications in our must-see, free exhibition.
From the trenches of the First World War to the latest in cyber security, Top Secret explores over a century’s worth of communications intelligence through hand-written documents, declassified files and previously unseen artefacts from the Science Museum Group's and GCHQ’s historic collections.
Trace the evolution of the gadgets and devices used to conceal crucial messages and to decode the secrets of others. Hear from GCHQ staff doing top secret work to defend against terror attacks and serious crime and discover the challenges of maintaining digital security in the 21st century.
Explore the story of Alan Turing and the team of Bletchley Park codebreakers who broke the Enigma code in 1941, uncover spy-craft from 1960’s Cold War espionage and challenge your friends and family to become codebreakers in our interactive puzzle zone.
Top Secret coincides with the 100th anniversary of GCHQ, the UK’s Intelligence, Security and Cyber agency.
Sign up to our What's On email newsletters to receive codes to break and a family trail to guide you round the exhibition.