7 September 1940 was the start of the The Blitz, the sustained strategic bombing of the United Kingdom by Germany during the Second World War. London was bombed by the Luftwaffe for 57 consecutive nights. More than one million London houses were destroyed or damaged, and more than 40,000 civilians were killed, almost half of them in London.
Bomb Sight [bombsight.org] is an interactive map that aggregates all the locations where the bombs fell between October 1940 and June 1941. As this data was previously available only in the Reading Room at The National Archives, Bomb Sight aims to make the maps available to citizen researchers, academics and students.
In the map, the bomb sites can be filtered by weekly time spans or only those that fell during the first night of The Blitz. In the future, the map should also include references to memories and photographs from the time period.
More detailed information about the data aggregation is available here.