The St. Clair River forms a vital waterway link between Lake Huron and Lake St. Clair. Ships from around the world ply its busy waters. A natural border between Ontario and Michigan, the St. Clair is known as "the world's busiest waterway." Exceptional vantage points from either shoreline allow interested observers to view the river's commercial and recreational activities throughout the year. returncharacterreturncharacterSt. Clair Shipping contains a wide array of images covering several eras, depicting the never-ending action and activities of this historic waterway.returncharacterreturncharacterAlann Mann has spent his life studying the St. Clair River and is a noted authority on the subject.