Mapping the Allied Bombing of Europe

This map of World War II Bombings helps to show how useful map legends can be. It does this by not having a map legend. The result is that the map's developer has created one of my favorite types of map game - 'Guess What is Being Mapped Here'.

The absence of a legend means that the user has to try to work out for themselves what the map visualizes. The first clue is that the map shows no bombs dropped on the UK during World War II. Therefore my guess is that it either shows bombs dropped by the UK, by America or by the Allies during World War II.

The lack of a legend also means that the map user has to guess what the size of the bomb markers represents. My guess is that the circle sizes either represent the number of bombs dropped at each location or the size of the bombs dropped.

Spoiler Alert - the answers to this particular map game are revealed below. If you want to work out for yourself 'what is being mapped here' stop reading now,

Of course the smart map user will notice the GitHub user name of the developer in the URL of the map. They will then do their own detective work and track down the map's GitHub repository. If you want to cheat in this way then you can discover that the source for the bomb data comes from the datamil Theater History of Operations (THOR) Data: World War II. The data actually represents "U.S. and Royal Air Force data, as well as some Australian, New Zealand and South African air force missions" from 1939-1945.

The map's GitHub repository also contains the GeoJSON file for the bomb data shown on the map. This GeoJSON file contains a 'Total Tons' property for each bomb dropped during World War II. Therefore the size of the map markers represents the total tonnage of bombs dropped on each location.


Now that we've worked out that the World War II bombings map shows Allied bombing missions we can move on to look at bombs dropped by the Luftwaffe on London. You can view a map of all the bombs that fell during the Blitz in WWII in London on Bomb Sight. To create the map the original 1940's bomb census maps were scanned, geo-referenced and the geographical locations of all the falling bombs were digitally captured.

You can click on all the individual bomb markers on this map to view details about the bomb and the damage caused and to view nearby photos taken during the Second World War. There's not so much of a guessing game involved in Bomb Sight. I'm going to be a little controversial and say that this map is all the better for including an information panel which tells the user what is actually being mapped.