When a huge earthquake hit Haiti a month ago, the jobs of rescuers and aid workers were made more difficult by the lack of information about the layout of Port au Prince.
OpenStreetMap is a collaborative project to create a free editable map of the world. This was the level of detail for Haiti’s capital at the time – major roads, no street names, no location of public buildings. Google's map had a little more detail.
But within 24 hours, two satellite firms released high-definition images of the island free of charge. This was a first, says Christopher Osborne, who works with OpenStreetMap. Users set about filling in the many blanks.
The map in this picture gallery shows the Cite Militaire district of Port au Prince. This is how its rubble-strewn streets looked on the ground in the aftermath of the quake.
As some 2,000 users added layer upon layer of detail to the map, aid workers and rescuers downloaded daily updates to help them make their way through the city from the airport, which lies to the top right of this area.
The Red Cross's Kjeld Jensen uses it on a handheld GPS. "Over just a few days, it saved me and my driver from getting lost twice, and the alternative would have been long delays. We are running fast trying to help people and your work makes it easier."
And a member of a US search and rescue team e-mailed OpenStreetMap to say what a boon it was to have downloadable maps with street-level detail. "Please be assured that we are using your data - I just wish we knew about it earlier."
As a result of the street-level detail, much-needed supplies of food, water and medicine could be brought in to those in need more easily...
... as planes queued at the nearby airport to off-load supplies and personnel.
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