Exhibition: Bletchley Park

One of the many ironies of the Bletchley Park story is that the code-breaking work carried out there was once the most secret activity of the Second World War. Now it is one of the best known, told in movies and in hundreds of books on the subject. Some historians argue that it helped to shorten the war by two years, saving tens of thousands of lives. Churchill memorably described the code-breakers (secretly, of course) as ‘the geese that laid the golden eggs and never cackled’.

So it is fitting that, with a recent Heritage Lottery Fund (HLF) award of £5 million and £3 million of match funding, a comprehensive new visitor centre has been built that not only places the work of Bletchley Park within the broad history of the war, but it explains clearly and cleverly the processes needed to read German signals traffic. First the signals have to be intercepted at listening stations; then they have to be decoded; then translated; then the intelligence passed on to whoever will find it of immediate value. Particularly effective are some of the interactive ‘games’ that appeal to all ages explaining the billions of combinations created by an Enigma or a Lorenz machine and the task faced by the code breakers in decrypting the signals.

Walking through the extensive grounds, the visitor can tour the well-restored huts where Alan Turing, Gordon Welchman and many others worked, which feel as though the code breakers have just popped out for a fag. Many of the huts have what Iain Standen, Bletchley’s CEO, describes as ‘set dressing’, with videos projected against walls and sound tracks adding atmosphere. Bletchley Park is strong on atmosphere, especially in the mansion house where the library and the office of the wartime boss, Alexander Denniston, have been beautifully restored.

Bletchley Park was saved in 1992 when a group of enthusiasts persuaded Milton Keynes council not to demolish it. From 1994, visitors started to arrive although there was not a lot to see except a few run-down, decaying huts and the mansion itself. Veterans from Bletchley Park often led tours, adding their own personal memories of working in such an extraordinary place. Clearly this was not a long-term solution and the new visitor centre and restored huts will provide context and insight for the next generation of visitors. Standen has ambitious plans to drill deeper into some specific wartime code-breaking stories and next year there will be an extension exploring the roots of British code breaking in the First World War. All this is much to be welcomed and Standen hopes that  250,000 visitors will be attracted to the site annually, a considerable number for an attraction an hour north of London. 

However, in one regard the visitor experience is not what it was before. Once the code breakers had got going by the summer of 1940, their principal challenge was to deal with the volume of signals traffic being intercepted with the speed necessary to make the intelligence valuable. In order to do this, they invented the modern computer. It used to be possible for visitors to see the replica of Colossus, the world’s first programmable electronic computer, lovingly rebuilt by the late Tony Sale for the National Museum of Computing. Indeed, it was one of the crown jewels of Bletchley Park. Now, the museum is a separate entity and Colossus is behind an eight-foot fence. In order to visit it, one has to leave Bletchley Park, take a lengthy walk and pay to enter the National Museum of Computing. Such a visit is highly recommended but too few visitors are likely to make the effort. 

The HLF and the Bletchley Park Trust, with support from corporate sponsors like Google, McAfee and BAE, are to be congratulated for the imaginative way they have restored Bletchley Park. But allow a day for your visit in order to take in Colossus as well and the story of the future development of the computer industry, which in the long run of history is probably the most important legacy of the remarkable story of Second World War code breaking.

Taylor Downing is the author of Secret Warriors: Key Scientists, Code Breakers and Propagandists of the Great War (Little, Brown, 2014).