Monks Mound
Collinsville, Illinois

Monks Mound is the largest man made earth mound in the world, approximately 100 feet tall, 955 feet long and 775 feet wide.  Atop this mound was a wooden structure temple with a continually burning sacred fire.  Monks Mound was at the center of Cahokia, the largest known community in North America before Columbus, inhabited from approximately 700 A.D. to 1400 A.D.  At Cahokia's height in 1100 A.D., there may have been 20,000 Mississippians in an area covering six square miles.  If you included the satellite communities, the number could have approached 40,000.  Cahokia was the greatest example of the Mississippian culture  and proof that full time agriculture could succeed in North America and foster permanent settlements.  The exact decline of Cahokia is unknown, but most experts point to a climate change, the Little Ice Age of around 1250 A.D, when Atlantic pack ice began to grow.  Combined with a lack of soil and water conservation, the region lost it's fertility and could no longer support Cahokia.  People believe that Native Americans were one with the land and only took what they needed.  I do not dispute examples of their ability to adapt to an environment, but Cahokia was an example of the opposite.  Ultimately, they left and lived in smaller settlements that were easier to manage. 

Cahokia was the largest community in North America
until Philadelphia surpassed it in population around 1800.

There are 155 steps to the top.  When I think about how this was built with what might have been 14 million baskets of 40 pounds of dirt each, I am astounded.  Cahokia has 68 of the 120 original mounds. Click on the link below for a map of the site. 

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