This detail of a hastily plotted Bomb Census Map records some of the destruction wrought by bombing in central London during the Blitz. © National Archives.

To keep track of the bombing of British cities during World War Two the Ministry of Home Security embarked on a Bomb Census Survey to provide a complete picture of raids across Britain so that an assessment could be made of raid patterns, types of weapon used and the consequent damage.

The bomb census began in September 1940, in London, Birmingham and Liverpool and by September 1941 it had spread to cover the rest of the UK.

Bomb Census Maps could be either a record of a single raid or, like this map of central London, a record of a two week period of bombing activity. © National Archives.

Regional technical officers of the Ministry of Home Security Bomb Census Organisation co-ordinated the collection of information in the field by local Civil Defence staff, such as Air Raid Wardens and the Police.

A network of War Rooms digested and summarised the information and sometimes collated it with intelligence from other sources. The reports were distributed to the Cabinet, Air Ministry, local authorities and to government departments with responsibility for civil defence.

A tracing from a raid in Manchester. © National Archives.

Some of the bombing raids were plotted directly onto maps whilst others were tracings - plotted on tracing paper over a map.

Today both the tracings and maps are held at the National Archives as well as in local archives and although their quality varies they provide a fascinating insight into the damage caused by Luftwaffe bombing raids during WWII.

The Blitz comes to Brighton - plotted between 1942 and 1944. © National Archives.

Click on the links below to see how bombing raids were plotted and recorded in some of the UK's cities.

London East End: Walthamstow Bomb Map Dating From 18 – 19 April 1944

Central London - A Bomb Map Plotting Activity Over A Two Week Period During The Height Of The London Blitz

Brislington, Bristol: A Bomb Map Showing April And August 1942

Bomb Census Manchester: A Single Raid On Chorlton

Bomb Census Liverpool: A Heavy Night Of Bombing

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