It's true that Google Earth already contains high-resolution satellite data for many cities and even some non-urban areas. But, Google Earth doesn't have Topographic Overlays just yet. Don't worry! Topo Overlays in Google Earth are possible by using what are called "KML Overlays". What is a KML you ask? Read more about what KML files are on Google. Once you have an understanding of what a KML file is, try reading and downloading some free KML overlay files. One reference is The Map Room blog, and also the Google Earth Blog.
Once you have a KML file ready for use, launch Google Earth and "open" the KML file and it's fairly easy to get Topo overlay data. This works great for soil survey professionals, land surveyors, bankers, appraisers, or basically anyone that shops with us here at EngineerSupply.com that is wanting a quick USGS Topo Map type of topo to overlay on a Google Earth Map. Within minutes you should be viewing Topo Maps in Google Earth!
