TopoView - A look at version 2.1
A tutorial by USGS scientist and topoView developer Chris Garrity demonstrating how to use topoView version 2.1. TopoView let's you access and download maps free of charge from the USGS's Historical Topographic Map Collection, published between 1884 and 2006.
An Introduction to TopoView (version 1.0)
Location Taken: Reston, VA, US
Topoview, a product from the U.S. Geological Survey
lets you access and download maps free of charge from the USGS’s historical topographic map collection,
published between 1884 and 2006.
We’ve redesigned topoView at version 2.1 with a new user interface that’s faster, easier to use, and more intuitive.
There are a variety of ways you can access the historical maps in the collection.
Probably the most common method is to simply enter a location in the location bar at the top of the interface.
Let’s find historical maps around New York City. I’ll enter Manhattan in my location tool, and choose Manhattan, NY from my dropdown list.
When I enter my location search, I’m instantly zoomed to the Manhattan area, and the map records table on the right is populated with all maps from the historical collection at that point.
You’ll see a marker in the interface indicating where the search return was generated.
Click or tap anywhere in the interface to move the marker, and the records table will be populated with maps at your new selected point.
At our selected point in the Manhattan area, we see there are 30 maps, filtered by all scales, throughout the full range of dates that span the collection.
Notice that my active record is expanded, showing additional information like map download, and preview options.
Simply click or tap any record to make it active.
By default, topoView sorts map records by date, with the oldest maps at the top of the list.
This can be easily changed by clicking any of the sorting buttons above the record table.
Your choice of sorting method will persist in future search returns.
Let’s preview the Staten Island map from 1898.
If I click the show icon, beneath the downloads section, the map will appear in the interface tied to its real world coordinates.
By adjusting the opacity slider that appears when the map loads,
I can easily compare the selected map to the underlying basemap showing the area as it is today.
This becomes especially useful when I want to observe changes in an area over time.
For this particular map, I can see what the area looked like before construction of features like Holland tunnel, and the Newark Liberty International Airport.
I can also observe the land-filled tidal flats area, that would eventually become Liberty State Park.
To download the map, I can choose from a variety of file formats in the downloads section,
including GeoTIFF, high-res JPEG, Google Earth KMZ, and GeoPDF.
Metadata information about the record can be quickly accessed by clicking the info icon below the downloads section.
For an isolated preview of the full map sheet, click the map thumbnail image on the right side of the active record.
TopoView makes it easy to navigate through the collection of about 180,000 maps.
We’ve added a variety of filters, enabling users to get instant access to selected maps of interest.
Let’s say I wanted to filter maps by date.
In this example, I’ll filter our map returns to show only those published between 1900 and 1940 at this point.
As I move the timeline sliders, you’ll notice the records table is automatically updated with maps published in my selected time frame.
In this case, I see that there were 15 maps published here between 1900 and 1940.
Applying these filters dynamically changes the content in the interface window.
This is useful when you want to visualize the extent of topographic mapping by the USGS throughout history
Let’s looks at the areal extent and number of maps published by the USGS in the contiguous United States between 1900 and 1920.
I’ll zoom to my area of interest and set my timeline sliders.
Notice that at the bottom of the interface the number of maps records currently in view is displayed.
In this case, we see that there are 8,469 maps that were published in our selected time frame.
The colors of the map footprints represent common USGS map series scales.
If I were interested in a certain map scale published during this time, I could click any of the buttons in my map scale filter to isolate that map series.
These are just some of the features available in the 2.1 build of topoView.
We invite you to try it for yourself at https://ngmdb.usgs.gov/topoview.
For a more detailed look at the interface, click on the link in the description below to view the tutorial released at 1.0.
It highlights additional features of the application, not seen in this video.