Google Earth lets you travel around the world not only in present time, but also in the past, thanks to archived satellite imagery. However these images only go back about 8 years, so if you’re looking for something older than that you probably need to use layers.
Layers are special Google Earth files with the KMZ extension that overlay extra information on top of the program’s map imagery, displaying details that are not available in Google Earth by default. And now thanks to David Rumsey you will be able to view and navigate hundreds of historical maps, from different countries and cities all over the world, right on Google Earth.
Rumsey has compiled an extraordinary collection of maps into a single KMZ file to use with Google Earth. It contains more than 200 maps, ranging from 1680 to 1930 and conveniently geolocated so that they appear exactly where they should be placed on today’s world globe. Some of them have had to be distorted in order to fit in with current cartography, as they were based on geographical misconceptions of previous centuries.
To install Rumsey’s collection of historial maps on Google Earth, simply download the KMZ file from his website and drag and drop it onto Google Earth’s interface. The maps will immediately be available on the left-side pane, under Places. They’re organized by continents, countries and dates. When you find a map you’ll like to see, just tick the layer and it’ll be automatically showed on top of the current map.
Rumsey’s maps have been carefully digitalized with high resolution cameras, but they still keep that characteristic look and feel of ancient documents: sepia color, tiny hand-written text, lots of margin annotations and of course, the map’s stamp, which includes the date of publication and the publisher’s name.