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Georeferenced Maps

This video demonstrates our main viewer for georeferenced overlays, and our related Side-by-side viewer for comparing two maps on screen. It illustrates how georeferenced map layers can be found and viewed, and how you can adjust their transparency to compare them to modern day satellite imagery. The various ways of searching are shown, as are the related tools for tracing features, and measuring distances and areas.


The Georeferenced Maps interface allows you to view a set or series of historical maps seamed together, in one continuous layer.

To search for maps in the Georeferenced viewer, first, choose the historic map series that you would like to view from the left-hand list. Then, search by modern placename, national grid reference, or historic placename, or use the map to zoom in to your place of interest. To zoom, use the plus and minus buttons in the bottom left, or use your mouse wheel. From here, you can switch between different map series that also cover your area from the left panel.

The Georeferenced Maps viewer has several additional features for you to explore.

The transparency slider bar allows you to change the transparency of the historic maps to display the background map behind it.

By default, the background map shows a modern ESRI satellite layer. To change to a different background map, select the drop-down list at the top of the page. Additional features are available along the top of your screen.

Full Screen / Draw mode provides a tool to mark up or draw on the map layers. The Draw tool allows you to choose a feature type and a colour and then draw features. You can move features once drawn, or delete them.

You will also find a 3D viewer option.

Finally, use the Spy viewer to view the historic map layer in a spyglass over the background map. You can change the size of the spyglass in the left hand panel.

The Side by Side viewer places georeferenced maps alongside modern maps. The 'Side by Side' viewer is accessible from the 'Side by side' link in the page header of both the Map Finder and Georeferenced maps viewers, as well as directly from the Map Images home page.

On a computer, you can rotate the maps by holding down the [Alt] and [Shift] keys, and drag with your cursor. On a mobile device or tablet, you can rotate the map using two fingers. To return to the default rotation, click the rotation arrow that appears in the top right fo your screen., or, refresh your page.

To save your current view as an image, you can Right-click on the map image and choose "Save Image As". This feature will work using Google Chrome, Firefox, or Edge browsers. When viewing an individual map, we also have a button along the bottom of the screen that reads 'Print PDF'. If you click this button, you can either print or save to your computer a PDF of your current view.