Watch Providers:
JustWatch makes it easy to find out where you can legally watch your favorite movies & TV shows online. Visit JustWatch for more information.

What strange forces saved one isolated section along the Upper Mississippi River from the repeated crushing and scouring effects of glaciers during the last two million years? And what pre-Ice Age throwbacks survived here in this unique geologic refuge that holds more Native American effigy mounds, petroglyph caves, strange geological features, and rare species than anywhere in the Midwest? These questions and more are answered in this captivating new documentary. A team of scientists embarks on a journey of exploration to expose both the science and threats behind three unique features of the zone - rare plants and animals, odd geological phenomenon, and striking remnants of a Native American pilgrimage like no other.
Watch Providers:
JustWatch makes it easy to find out where you can legally watch your favorite movies & TV shows online. Visit JustWatch for more information.

January 09, 2013

November 05, 1999

January 17, 1994

February 15, 2013

January 19, 1991

March 06, 2005

March 01, 2001

June 04, 2017

February 19, 2019

October 17, 2004

November 21, 2023

September 18, 2009

March 18, 2010

January 31, 2026

December 14, 2022

January 01, 1995

July 04, 2014

January 01, 1954

April 24, 2019

July 18, 2018