Inside The National Museum of Computing, Bletchley Park

The National Museum of Computing is an independent registered charity based in Block H at Bletchley Park, Milton Keynes, MK3 6EB. Block H was the world's first purpose-built computing centre, and it housed six of the ten Colossus machines in use at the end of the Second World War. The building is Grade II listed, and the museum is housed inside it. The museum was incorporated as a company in 2005 and was established in 2007. Its working Colossus rebuild stands in the original room where Colossus No 9 stood during the war. Tony Sale led its construction between 1993 and 2008.

The collection follows computing from the wartime codebreaking machines through the mainframes of the 1950s to 1970s and on to the personal computers of the 1980s. The Bombe Gallery has a replica Bombe, while the Tunny and Colossus Galleries display a Lorenz SZ42 and a Heath Robinson, alongside the Colossus Mark 2, which weighs five tonnes and has 2,420 valves. The First Generation Gallery includes an EDSAC replica and the WITCH (Harwell Dekatron), which the museum describes as the world's oldest working digital computer. Other areas include the Large Systems Gallery, the PC Gallery with a BBC Micro, Sinclair, Amstrad, Osborne 1 and NeXTcube, the Simulation Gallery with a Cray-1, and the Software Gallery. The BBC Classroom has vintage BBC Micros, and the Pop-up Gallery hosts temporary exhibitions. The collection is made of functional historic computers rather than only display pieces.

The museum is open on Tuesdays, Thursdays, Saturdays and Sundays. Winter hours run from 10:30 to 16:30, and summer hours extend closing time to 17:00. Advance online booking is recommended, although same-day visitors are also admitted. Tickets come as individual, family and Annual Passes. An Annual Pass is a physical pass, completed with your name and signature at Admissions, and it is valid for 12 months from your first visit. Children under 5 enter free, as do companions of people with disabilities. Day passes are non-refundable except in exceptional circumstances. Online tickets are valid only for the date shown and do not guarantee parking. The museum has its own entrance fee, café and gift shop, and it is separate from the Bletchley Park Trust. It relies on ticket sales and donations and receives no public funding. Bletchley Train Station is the nearest rail stop, and the museum is also easy to reach by car. Online group bookings are for up to 10 visitors, while groups of 11 or more must contact the Bookings Team. The museum also runs a learning programme for schools and colleges, and learning visits must be booked in advance.

Recent events include the designation of Colossus as an IEEE Milestone, celebrated on Tuesday 29 September 2026. The same day, the 2026 Tony Sale Award was presented, with the hardware restoration award going to David Lovett of Usagi Electric, and former museum director Jacqui Garrad received an Honorary Fellowship. Coming up, the museum will celebrate 75 years of LEO I with the LEO Society on Sunday 29 November 2026, and a limited number of tickets are on sale. The online shop sells 10th anniversary items, including limited edition framed prints of the Enigma, the Turing-Welchman Bombe and the Lorenz at £89.00 each, and the Total Turing Bundle from £125.00. There is also an Adopt an Artefact scheme, with Silver, Gold and Platinum levels, where adoptions last 12 months.