The National Museum of Computing

The National Museum of Computing is located on the secret wartime codebreaking campus of Bletchley Park.
You can see: a rebuild of Colossus, the world's first modern computer in action (used during World War II to crack Nazi codes); the WITCH, the world's oldest working digital computer (it's the size of a wall and flashes and clatters as it calculates) and big iron" computers that look like washing machines.
You can try out: the first home and school computers from the 1980s; the famous 1986 school's BBC Domesday project on the original laserdisc technology; and the 2011 Domesday update on today's Touchtable that is like a huge iPad.
You can even try your hand at coding on BBC computers from the 1980s."