(Left) The release of topoView lets the public discover and use USGS historical topographic maps through a new, innovative Web interface.
The USGS National Map program, working with the National Geologic Map Database(NGMDB) project, has launched a new version of the beta application, topoView for exploring, viewing, and downloading the more than 178,000 USGS digitized legacy topographic maps from the USGS Historical Topographic Map Collection (HTMC). These scanned quadrangle maps, georeferenced at various scales, dating from the late 1880’s to 2010. For more information on the effort to capture the complete map collection, see the Historical Topo Map Collection web site.
(Right) Introducing the new “topoView” home pageGetting Started is Easy
This innovative web interface has been designed and released to the public in order to evaluate new ways of exploring the map collection. With topoView, you can search and discover maps starting with a map of the United States. A comprehensive list of tips and hints on how to get the most from this interface are in the “Help Pages” and the YouTube “Quick Start Video”
Left) Finding a location on topoView. Here, the street address of the USGS National Center in Reston, Virginia was typed into the Location box.Finding a Map
Here’s an example of how to find a map — by entering some locality information into the search box on the right side of the screen, such as a street address, geographic feature, or lat/long coordinate pair, the application will zoom to the requested location.
Selecting Your Map
Once you click on your desired area, a small map information box will appear in the lower left part of the viewer. Along with a thumbnail view of a sample map, features in this box allow you to select the download format, get a larger version of the preview map by clicking on it, and see how many different historical maps are available for that area. From there, a small information box will appear in the lower left side, along with a key of the map scales available to the lower right.
When clicking on or near the location pin, the “map information” box appears in the lower left corner of the map. The light red overlay is a result of selecting “show all” maps option from the “map scales” box – the red color indicates that a 1:24,000-scale map is available for that area.
(Right) By clicking on the “number of maps” circle in the map information box, a list of all availablemaps is displayed. In this case, 35 historical topographic map scans are available for selection and download, from 1880 to 2010.
Map Scales
Topographic maps are made in several levels of detail, or scale. You can select the map scales you’d like to browse, by using the small “map scales” box on the right side of interface. To see every available map, select “show all” and use the color as a guide to each map scale.
Maps Through Time
Another unique addition to topoView is the “timeline” slider at the top of the application. This feature allows you to or chose a time period by dragging one or both sliders. The slider also enables you to see the progress of mapping across a desired area or the entire US through time.
How Many Maps?
When you click on a map, the small map information window that appears in the lower left corner also indicates how many maps are available for that selected area. By clicking on the map counter number, you can see a “map records” table that lists all of the available maps, map names, dates, and other details. The record results can also be sorted or filtered to help you browse the list as you wish.
You can sort the map records list by clicking on the various sort tabs. In this example, the list is sorted by date, showing the oldest map available. Click on a map record, and you’ll see the thumbnail and details for that map.
You can further filter your desired maps. In this example, the “slider bar” at the top of the application was set to all maps, all scales, from 1940 to 1960. By this filtering, the number of maps drops from 35 to 10.
Getting Your Map
Because of customer and user requests, topoView offers the topographic map in these popular formats to download:
- JPEG
- KMZ
- GeoPDF
- GeoTIFF
