A lot of people have been interested and excited about the new USGS Historical Topographic Map Explorer

So this may also be of interest:

ESRI Story Maps have become popular information sources when helping library users:

Selected example collections: 

Events and Disasters:

Infrastructure and Planning:

Nature and Environment:

Science and Technology:

A list of all Story Collections:

..And if one would love to learn more about maps:

ESRI Free Online Course:
Go Places with Spatial Analysis

Enjoy the day,

Emily Wild
Librarian (Physical Scientist)
U.S. Geological Survey
Denver Library
Box 25046, MS 914
Denver Federal Center
Denver, CO 80225-0046
ph: (303) 236-1003
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