Guest Post: Research, research, research – Google Earth


The first thing to a good relic or coin shoot is doing your research. This might entail going to a location and “scoping” it out, or to the library to look at old maps.

Better yet how about both? Yes this is possible with the technology we have today. We can literally scope out a current site and look at an old map at the same time!

This is where Google Earth comes in handy. Google Earth “GE” is a free application ( there is also a fee based application called GE Professional) that you can download from Google that allows you to view current maps and aerial views of areas along with around 1000 other options. In this article I will only touch on one, the ability to “overlay” an older map on top of an aerial view to get a good approximation of how things look now compared to how things looked then.

After loading Google Earth lets look at some of the common functions and allow us to get our bearings with the task at hand.

I am assuming that you are a little familiar with GE, but I will go over a cursory outline of what it can do.

GE is very nice in the fact that it like all good programs take full control of the scroll functions in mice. The scroll function allows you to zoom in and out of the field of view. Right mouse clicking on the view allows you to “pull” your map into any direction you want allowing you to pan through sections with ease. Notice that the maps orientation is due north (the compass is in the upper right hand corner) getting comfortable with the compass will help with placing an overlay map. This is due to the fact that all maps in the Northern hemisphere are centered with north being in the “up” position. Getting familiar with panning and the compass is a must when working with the older maps as overlays.

Getting used to GE is very simple here are some tips on using the places and layers windows.

Notice that all places and layers are located on the left of the screen. This allows you to turn on/off features and allows you create “layers” to your views. On the layers menu you can turn on roads and other features that allow you expand or limit the amount of data that is displayed on your map. Expanding the “+” sign will allow you to drill down and see each individual option available under each layer heading.

Here I have expanded transportation and have put a check mark next to railroads enabling all railroad lines to be displayed on your view. The places window will allow you to add your overlay. This feature will allow you to turn on and off places of interest, overlays, polygons and paths.

After you have played with GE you will notice the power of what you have in front of you. The sky is the limit! Next let’s explore overlaying an old map on to GE. Old maps of your area can usually be found on the internet. Google is a great place to start your search for a “digital “version of a map. There are plenty of free maps on the internet that will help you in your quest.

Let’s get to the task at hand. After finding a good digital map, open up Google earth and type the location of where you want to do your hunt. Make certain that your compass is facing north! * For you Southern Hemisphere folk “South”*

Look at your digital map you want to overlay and get the approximate expanse of the map to mirror your area in GE. For example if your map shows parts of a lake in the digital map try to approximate the area shown in GE. This is VERY helpful when placing the overlay.

On the top row of GE you will see an Icon that looks like “layered papers” This is the Overlay tool, click this Icon. Here you will see a border box appear in the “View” mode this will approximate where the map placement and size of the map. This can be adjusted so don’t worry if it’s not exact.

Enter in a useful name on your overlay and browse to where you stored your digital map. At this point you will see your overlay on top of the current view. Keep the link box open as you will be able to adjust the transparency of the map by the slide tool on the description tab. The transparency tool is nice because you can view either the map or the current view and adjust if you want to see both. The more “opaque” the object is the more solid it looks. The more “clear” allows the map to blend in with the background.

You may want to turn off unwanted features to allow you to see the overlay better. On the placed map you will see a cross hair ( in green) on the object, by touching this with the mouse you can move the map on the background to align it with your static features on your background map, rivers, lakes, roads ( if they existed) and other land features are good points use to place the map properly. By using the cross hair and the side border adjustments you will be able to “resize” the map to come close to what is actually seen in the view. This process at first can be a bit frustrating if you make too many adjustments at one time. A bit of patience and practice and you can master this overlay in less than ½ hour. One thing to note, all maps are not created equal. There are many maps which are not truly accurate this isn’t necessarily a bad thing as they approximated just as we do today its only human nature. The other fact is that there are different projections that are used in maps but I won’t get into this discussion here.

Remember to use your transparency adjustments to allow you to see through your digital map and see the background. This will make all the difference in the world!

At this point you can close the overlay control box and you will see your results! To change the transparency right mouse click on your new place and click properties. This will bring up the overlay control box and allow you to adjust the transparency. Now the real work begins! Time to find that homestead that used to exist! Enjoy!

This is just a taste of what you can do with Google Earth. There are many features that allow you to expand your research capabilities in the field of metal detecting. As I mentioned earlier research is the key to a good hunt. But most of the fun is still the detecting.

J.J. Antonetti

Google and all trademarks are property of Google Inc.

Author: J.J. Antonetti

No Responses to “Guest Post: Research, research, research – Google Earth”

  • Jack C Says:


    Have you ever used handheld GPS units with GoogleEarth? I’m thinking about purchasing a unit for hunting/hiking, but thought it would be cool to use it with GoogleEarth. Is this possible with the free version to plot waypoints directly into it? I’m not seeing it off hand.

    I think using GoogleEarth with map overlay coupled with GPS coords to plot structures or find locations would be a cool way to really document a hunt site


  • JJ Says:

    Although I don’t work for Google I do know that it is compatible with several different versions of Linux, OSX and also Windows. There is also a slew of different options to choose from, including gps integration ( Google Earth plus a $20 upgrade) and also GE Mobile which allows maps to be displayed on phones. There are literally 1000’s of solutions when it comes to Google Earth. Visit for a comparison of all their products.

  • Oscar Says:

    I use a handheld GPS with Google. I dont interface the two but I do use GE GPS location info and input it into my GPS device to help me locate the exact spot I want to go. I just tried this the other day where a spot I wanted to go ended up being in a very dense wooded area. If I did not use my GPS and knew where I wanted to go I would never have found it or even may have gotten lost.

  • JJ Says:

    Fantastic use of both tools! Kudo’s to you. Did you find what you were looking for? The research end and the ability to find it in the end seem to go hand and hand..

  • mlamp20412 Says:


    Downloaded Earth, neat program. I get similar results using online county GIS/real-estate info in my area and a Streets 2002 program. I like the idea of map import and overlay, but I did not see how to scald or rotate to make the later useful. Any advice?


  • JJ Says:

    Yes you can scale and rotate, but as I stated in my article the first thing you need to do is orient GE to due North ( using the the compass on in the upper right hand corner) Then go to your area that you are going to overlay after that is done you can select your overlay and pull the corners to match the backgound map, make sure your overlay is selected and you will see green corner markers which will allow you to stretch and manipulate as needed.
    I hope this helps!

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