Soo Locks & the St. Marys River

The Soo Locks at Sault Ste. Marie, Michigan attract half a million visitors annually to watch ships navigate the 21-foot change in elevation between Lake Superior and Lake Huron.  The St. Marys River is a 74.5-mile-long dynamic waterway that is the economic backbone of the United States.  An average of 23 ships a day carry billions of collars worth of cargo through the River and serves as a vital waterway, transporting coal, wheat, corn, stone, petroleum products, and primarily iron ore. This ore is crucial for steel production, which is essential to the nation's manufacturing industry.  Inhabited for thousands of year, the St. Marys River connects Lake Superior with the other four Great Lakes, and the wider world.