In the days since the earthquake in Nepal, thousands of humanitarian mappers have sprung into action to fill in gaps in the map in the affected area. In addition to the 3960 previously mapped miles of roads and 182,706 buildings, more than 2000 mappers have recorded 13,199 new miles of roads and 110,681 new buildings.

In many post-disaster mapping cases there is little existing map data in cities, but in this case Kathmandu was already well mapped and the major challenge has been to fill in surrounding rural areas. The animation above shows the data that was present three days ago and all the new work that has gone into mapping thousands of miles of roads since then.

See the Humanitarian OpenStreetMap Team wiki to learn how you can help.