Historical Topographic Maps

Topographic Maps

Explorers need maps.  The U.S. Geological Survey has been creating and updating these maps since its inception in 1879.  If you need a current map for your explorations,  you can download them for free or order them on paper using the “Map Locater & Downloader” at store.usgs.gov.

Beyond current maps,  the U.S.G.S. now has historic maps available.  These are very important if you have an interest in history or changing topography over time.  They are perfect for the historical explorer that is out to find old wagon roads, mines or other cultural artifacts.  They are also helpful if you are trying to find a location based upon an old description that no longer matches what is now out there.  If you are interested in the ecology of an area,  you can use the old maps to determine where marshes, vegetation and waterways were so that you can compare them to their current locations and extent.

USGS Historical Map Explorer

The USGS Historical Map Explorer is available at historicalmaps.arcgis.com/usgs/.  To use it, start by searching for the location of interest.  Once there, click and hold the mouse button for a second and a timeline will appear at the bottom of the page showing you the available maps.  When I did that for Klamath Falls, Oregon, where I live, the system found maps from 1889, 1894, 1955, 1958, 1985 and 1991. The 1889 and 1991 versions are shown below.

The Map Explorer allows you to have all the various maps for an area open at once.  They are arrayed one atop the other in layers.  You can adjust the opacity of each layer to look at one or more than one map through other maps.  It also puts a red ‘X’ on the map where you clicked.  The red ‘X’ is helpful if you want to print the different maps and be able to quickly match them.  You can easily see the red ‘X’ on the 1991 map, below, then find it in the same position on the 1889 map.

It looks like the USGS did a pretty good job of getting the maps adjusted so that all the overlays are to the same scale. You are still likely to see some movement in positions of landmarks from map to map as both surveying and map making capabilities have improved over time.

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