South Dakota

Historical Chronology.  A fairly extensive timeline, with numerous images, that details the history of South Dakota.  Created by the State Historical Society.  [ccr]
http://www.sdhistory.org/soc/soc_hist.htm

Geology, agriculture, and water resources.   Seven virtual tours with excellent photos and descriptions of environments all over the state.  Each tour can be accessed from a clickable map.  Tours include:  Geology (Eastern, Central/Western, and Black Hills), Crop Agriculture and Soil (Eastern and Central/Western), and Water Resources. This comprehensive site is from the Plant Science Department at South Dakota State University.  [ccr]
http://plantsci.sdstate.edu/woodardh/