We have in the past looked at a lot of content provided by the USGS. The USGS is the provider of the data for the ‘earthquakes layer’ in Google Earth. We also looked at some of their future plans, like the 3D Elevation Program (3DEP).
We recently came across this article about USGS’s topoView. Despite its name, it is not for actually viewing maps but rather, it helps you find and download them. The maps in question are historical topographic maps of the US from the USGS’s vast collection.
USGS topoView
The maps can be downloaded in various formats, including KMZ for viewing in Google Earth.
A topographic map of Fort Smith, Arkansas, from 1887.
We found it interesting in the Fort Smith map above just how much the river has changed since then. When you have downloaded a KMZ and loaded it in Google Earth, expand it in ‘Places’, find the ‘Map’ item, right click and select ‘properties’. In the Image overlay dialog box that appears you can adjust the transparency of the map to compare it with the modern imagery in Google Earth.
About Timothy Whitehead
Timothy has been using Google Earth since 2004 when it was still called Keyhole before it was renamed Google Earth in 2005 and has been a huge fan ever since. He is a programmer working for Red Wing Aerobatx and lives in Cape Town, South Africa.
The National Library for Scotland (NLS) provide a similar free on-line service for historic, out of copyright maps from the national mapping agency, Ordnance Survey, in Great Britain. Large scale maps for London, Edinburgh and Glasgow can be found as KLM files in theGoogle Maps Gallery, and comparing Street View to the cities as mapped around a century ago is fascinating. The NLS site also has many more historic maps with extensive coverage in GB with a Bing Maps ‘satelite’ underlay accessed through a slider (they recently dropped a Google Map satelite imagery underlay !)
It would be interesting to hear of comparable examples in other countries.