U.S. Coast Survey Civil War Era Maps

The United States Coast Survey, now part of NOAA, has been in charge of mapping the coastline of the country since 1807.  These geographers, oceanographers, and cartographers proved the importance of geography during the Civil War (1861-1865) by providing the Union military detailed maps of the Confederate coastline and naval defenses. 

Now NOAA has made these hundreds, if not into the thousands, of maps available online.  This site is a dream come true for map and Civil War buffs.  Be sure to check it out!  (Hat Tip:  Matt Rosenberg's Mrgeog Twitter Account)