Mackinac Island Limestone Formations


Arch Rock


Arch Rock is a breccia rock formation that was formed by winds eroding away the softer rocks around it over time.  It rises 146 feet above the water level and can be seen from many different spots on the island.  In Ojibwe legend the arch is the gateway through which the Great Creator entered to get to his home in Sugar Loaf (below).


Sugar Loaf

Sugar Loaf is a dramatic breccia formation that rises 75 feet above the ground and is the largest of Mackinac Island´┐Żs many limestone stacks.  Centuries ago, Lake Algonquin covered all but the center of Mackinac Island, leaving only Sugar Loaf protruding from the water.  When the water receded, the rock formation remained standing as a tower of rock.  Ojibwe legend says that Sugar Loaf was the dwelling of the Great Creator or Great Spirit Gitchie Manitou.



Page created by Andy Stewart, a GEO 333 student

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