C Block

C Block was the 'master-index' section, vital in record keeping and cross-referencing of intercepted German messages.

Photo: C Block © LSA Aug 2015.

| Blocks: A | B | C | D | E | F | G | H | Location | Photo Gallery |

History

C Block, during the war, was the card index section of the code-breaking organisation, using Hollerith punched-card reading machines to process the huge amounts of data which had to be cross referred.

GCHQ (Government Communications HQ) ran its CTS (Central Training School) between 1946 and 1987.

News Releases

27th June 2012 - News Release

In September 2011, the Bletchley Park Trust announced that it needed to raise £2.4 million in match funding in order to unlock a Heritage Lottery Fund grant of £5 million. The Trust is today delighted to announce that these funds have now been successfully raised and that the Heritage Lottery Fund has granted the Trust “Permission to Start” on the restoration project.

	C Block: 'SORRY MY DECOR IS LACKING, BUT POST-REFURB I'LL BE JUST CRACKING'. Photo: C Block, soon to be refurbished © LSA June 2007.

Urgent restoration is due to start on Huts 3 and 6 as well as C Block.

Googling in the Park

On 4th August 2011, Google lent its support to Bletchley's campaign to raise funds for the restoration of C Block and sent a Street View camera to capture off-road images of the site. The 360 degree camera was mounted on a specially adapted tricycle.

Grade II Listing

"On 6th Jan 2012, heritage minister John Penrose awarded a Grade II listing to Block C which housed the site’s first use of high-speed data processing machines on a large scale which greatly sped up the code-breaking work, previously done by hand. Its hardened exterior and soundproofing show the importance placed on protecting the Hollerith machines and card data inside."

Main Entrance
	The new main gate from 2014 with the restored C Block makes an impressive visitor centre. Photo: The new main gate from 2014 at the rear of C Block © LSA August 2015.
Pre-Restoration
	C Block was the 'card index' section, vital in record keeping and cross-referencing. Photo: C Block, boarded up and overgrown © LSA July 2007.
	C Block as viewed from the first floor of B Block. Photo: Across the rooftops, C Block before restoration © LSA June 2012.
	C Block as viewed from the first floor of B Block. Photo: Across the rooftops, C Block before restoration © LSA June 2012.
	C Block during restoration. Photo: C Block enclosed as the restoration commences © LSA June 2013.
Photo Gallery
	Photo gallery of C Block from 1999 to 2015. Photo: C Block © LSA October 2012.
Location
	How it was: Screenshot showing location within Park. Map/image © 2007 Google and Infoterra Ltd & Bluesky, The GeoInformation Group.

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