Bletchley Park is an English country house and estate in Bletchley, Milton Keynes (Buckinghamshire), that became the principal centre of Allied code-breaking during the Second World War. During World War II, the estate housed the Government Code and Cypher School (GC&CS), which regularly penetrated the secret communications of the Axis powers – most importantly the German Enigma and Lorenz ciphers. The GC&CS team of codebreakers included John Tiltman, Dilwyn Knox, Alan Turing, Margaret Rock, Mavis Lever, Harry Golombek, Gordon Welchman, Hugh Alexander, Donald Michie, Bill Tutte and Stuart Milner-Barry.