Bletchley Park first appeared as a private residence in 1877 when architect Samuel Lipscomb Seckham purchased the land and constructed a house upon it. Sir Herbert Samuel Leon acquired the estate in 1883 and expanded the structure into what one architect described as a maudlin and monstrous pile combining Victorian Gothic, Tudor, and Dutch Baroque styles.
Admiral Sir Hugh Sinclair head of the Secret Intelligence Service bought the site using £6,000 of his own money since the government lacked budget approval. Sinclair selected the location for its geographical centrality near Bletchley railway station where the Varsity Line met main routes connecting London to northern cities.
The first operational unit of the Mark 2 Colossus computers was ready on the 1st of June 1944 just before D-day landings. Flowers produced one Colossus monthly for the remainder of the war creating ten complete units plus an eleventh part-built machine.
Not until July 2009 did British government fully acknowledge contributions by striking a commemorative medal bearing inscription GC&CS 1939, 1945 Bletchley Park and its Outstations. The formal posting for many Wrens working there was HMS Pembroke V while RAF names included Eastcote Lime Grove and Church Green.
Milton Keynes Borough Council declared most park area conservation area in February 1992 enabling visitor access starting in 1993 followed formal inauguration by Duke of Kent in July 1994. Bletchley Park Trust formed in 1991 with initial trustees Roger Bristow Ted Enever Peter Wescombe and Dr Peter Jarvis protecting land from sale for housing development.