Complex sentence: This land area of the Burt Lake Band was approximately 20 miles inland, due south of the Michigan's Straits of Mackinac, an area of water separating Lake Michigan to the west from Lake Huron to the east.
Split into simpler sentences: This land area of the Burt Lake Band was approximately 20 miles inland due south of the Michigan's Straits of Mackinac. An area of water separating Lake Michigan to the west from Lake Huron to the east.