On November 9th 2024, the National Museum of Computing (TNMOC) commemorated the 80th anniversary year of the Colossus code breaking machines with the unveiling of a prestigious World Origin Site plaque, recognising Colossus as the world’s first electronic, digital computer. This milestone was celebrated at TNMOC, located within Block H at Bletchley Park, the only surviving building where Colossus machines were deployed during World War II.

The plaque was unveiled by Alan Bealby, Chairman of the Post Office Remembrance Fellowship, honouring the crucial role of General Post Office (GPO) engineers in Colossus’ creation. These engineers, led by Tommy Flowers, built Colossus to break the wartime German Lorenz cipher, contributing significantly to the shortening of World War II.

Alan Bealby (PORF Chair) and Martin Wilkie (Founder of WOS UK) shake hands in front of the newly unveiled Colossus WOS plaque, in front of the Colossus rebuild at TNMOC.

The National Importance of Colossus and Block H

Speaking about the importance of the World Origin Site plaque, Jacqui Garrad, Museum Director at TNMOC, said: “Colossus has always been a source of immense pride for us, but it can be difficult to convey its global importance to our visitors due to its lengthy classification under the Official Secrets Act. This World Origin Site certification firmly establishes Colossus as a true world first in the history of computing. Not only do we have a working reconstruction at TNMOC, but the fact that it is still here, on the very site where Colossus No.9 operated, makes this a landmark story. An absolute world first in so many ways. The World Origin Site plaque strengthens our ability to share this remarkable story for decades to come.”

More Than Just a Plaque 

The World Origin Site plaque unveiling was complemented by the opening of a temporary exhibition honouring the legacy of the GPO engineers who worked on Colossus. The exhibition, titled ‘The Hidden Figures of Colossus’ is dedicated to the unsung GPO engineers whose ingenuity and dedication helped bring Colossus to life. The exhibition features original design plans, rare transcripts of interviews with figures like Tommy Flowers, as well as artefacts on loan from GCHQ that shed light on the human stories behind Colossus. This exhibit aims to reveal the individuals who were crucial in developing Colossus but were often overshadowed by the secrecy surrounding their work.

 Colossus.PORF Trustees with the Colossus Computer 9th November 2024

The Post Office Fellowship of Remembrance are delighted to have funded the restoration of Block H at Bletchley Park.

The funding will enable the Museum to continue to demonstrate the unique working reconstructions of World War II code breaking machines including Tunny, Heath Robinson and Colossus.