Colossus computer — Colossus 10 with its extended bedstead in Block H at Bletchley Park in the space now containing the Tunny gallery of The National Museum of Computing
Photo Credit: By Good, Jack; Michie, Donald; Timms, Geoffrey (1945), General Report on Tunny: With Emphasis on Statistical Methods, UK Public Record Office HW 25/4 and HW 25/5 - Public Domain, https://commons.wikimedia.org/w/index.php?curid=52298957