The Maps team at ETH Library is rendering 1,135 digitized map sheets from its historical holdings accessible via the platform oldmapsonline.org (external link) and the mobile app "Old Maps Online (external link)".
The maps are also being connected to the Georeferencer (external link) tool so they can be georeferenced more precisely for further academic use and integration in geoinformation systems (from Google Earth to professional visualisation and analysis software such as ArcGIS or Quantum GIS). The maps are now to be indexed via crowdsourcing.
Would you like to participate in this campaign?
All you need is an account: either an existing Google, Facebook or Twitter account, or a Georeferencer account.
Current status of georeferenced maps
Step by step
- Click on the button displayed above. A random map from ETH Library's holdings will open in Georeferencer and be juxtaposed against a modern map (Google Maps, Open Street Map).
- Gain an overview of the two maps (moving, zooming). Based on the corner coordinates already recorded, the historical map will lie approximately in the extract of the modern map.
- In order to georeference the map, place points of reference that coincide geographically on both maps. The more points you place, the more accurately the map will be located.
- When you would like to complete the process, click on "Save". The georeferenced map will then be overlaid on the modern map so you can see whether it has been located correctly.
For more detailed instructions, consult the following video and the comprehensive handbook of the British Library crowdsourcing project.
Georefencer (external link), by British Library