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Mapping and GIS Lessons for Poets, Historians, and Scientists: Google Earth Basics

CS-X Module created by Emily Fairey, Brooklyn College OER Developer

Google Earth: Placemarks, Paths, Layers, and Legends

  • Download a historic map (as an image, not as a kml layer) and add it to GE as an image overlay
  • “Georeference” it over the GE interface using at least 4 "control points."
  • In GE, name and describe this layered map, and export it as an image and as a kml layer.
  • Explore the other map repositories listed here, such as NYPL Map Warper, ArcGIS Esri, and GE Map Database.


It is also feasible to search for features manually, through the Google Earth navigation.






Download an image of an historical map to your PC.

Now, using the image overlay icon image overlay icon open the image in Google  Earth.

  1. Click the Add Image Overlay button to add a new image overlay. A New Image Overlay dialog box appears, and a green outline is placed on the Earth.

  2. In the New Image Overlay dialog box, type in a name for the image overlay in the Name field. 

  3. Copy and paste the link below into the Link field, or click "Browse..." and find an image to add from your local hard drive. In this example, we will use the following picture.

  4. Move the New Image Overlay window aside to see the Google Earth Viewer. Do not close the window or you will be unable to edit the map. (If you did close it, you can open it again by right-clicking the new image in your folder and selecting Properties.)

  5. Use the green diamond to rotate, the green cross to reposition, and the green handles to stretch the overlay until it matches the imagery beneath. This may take a bit (or a lot) of tweaking to match up the detail, and it may never match up perfectly.

  6. Move the Transparency slider to the left to make the image a little transparent, which will assist you in placing the image in the correct location. Use the park boundaries to help you align the park boundaries on the map with the boundaries in Google Earth.

  7. Use the center cross-hair marker to move the image overlay on the globe and position it in the right location.

  8. Use the triangle marker at the left to rotate the image for better placement.

  9. Use any of the corner or side anchors to stretch or skew the selected corner or side. If you press the Shift key when selecting this marker, the image is scaled from the center.

  10. Click OK when you are finished. The map is now listed in the Places panel, and can be saved to a KML file with other Google Earth project data you have created.