On 18 January 1944, Bletchley Park took receipt of a machine so big, it was rightly called Colossus. It took months of design work between Bletchley Park and the General Post Office (modern-day BT), based at Dollis Hill, before it was built. This machine was going to help speed up the Codebreakers’ work on Lorenz, one of the most fiendish ciphers of World War Two. Today, Colossus is hailed as the world’s first large-scale electronic digital computer. Head to our X (Twitter) feed where we’ll be m