Georeferencing

Georeferencing

The British Library’s Georeferencer project is crowdsourcing location data to make a selection of its vast collections of maps fully searchable and viewable using popular online geotechnologies.

Published date:

Online geographic tools allow historic maps to be overlaid on modern mapping, enhancing the ability to view and compare the past with the present and improving findability. Georeferencing, i.e. assigning points on a map image to corresponding geographical coordinates, links the map to its spatial location on the ground using universal geographic standards (latitude / longitude).

Background

The British Library began a project to crowdsource the georeferencing of its scanned historic mapping in 2011 by partnering with Klokan Technologies to customise its online georeferencing tool. There have been five public releases of maps since 2012, all of which met with tremendous success. In total over 8,000 maps have been “placed” by participants and subsequently checked for accuracy and approved.

Results

Through georeferencing, the selected map images were spatially enabled, making them geographically searchable and able to be visualised using geospatial tools and combined with other maps online. All georeferenced maps are added to the portal Old Maps Online, which uses a geographic search interface to identify and view historic maps from numerous collections online.

The output of this work may also be viewed using the BL Georeferencer interactive map and directly from the Online Gallery map pages

Further information

Any queries about this project should be directed to georeferencer@bl.uk. To connect with other users of this technology and participate in discussions, join the User Group of our technology supplier, Klokan Technologies.

See also

Subjects

Maps

The British Library collection of maps, plans and views is one of the largest in the world, numbering some 4.5 million