National Museum of Computing

If you’re interested in computers this place is well worth a visit. The replica of the original Colossus computer (the first computer that was ever designed to perform a task in anger) is here, and it’s a marvel watching it work.
The tour is definitely worth it. You get a tour guide who’s clearly passionate about what they do there, and a pretty good introduction to cryptography to boot.
The pass lasts a year and it’s well worth using it to visit again if you missed anything the first time. Almost everyone is a volunteer and you’re greeted by friendly faces and fascinating facts wherever you turn.
Finally, if you’re British it gives you a real sense of national pride reading about what was achieved here during the War.

Bletchley Park is so many things. A park, yes, but it is a park filled with visitor attractions including the National Museum of Computing. The museum is developing gradually and houses a lot of equipment, some of which is interpreted. Collossus was the first real computer and was developped here. Bletchley Park is most famous for its wartime role in fighting the intelligence war, and is a heritage site because of that celebrated past. Here large teams worked secretly to crack the codes used by Germany and their success was enormously important to the war effort. There are far more things to do here than can be covered in a short review, suffice to say that a full day should be allowed if you are a first-​time visitors as there is lots to see. Special event days are regularly held with themes and demonstrations. If you get a chance to see a re-​enactment of a wartime RAF control room, don’t miss it.