4. The St. Lawrence Seaway is a massive seaway combining USA and Canadian waters. Besides being a major seaway for trading the St. Lawrence Seaway is a major source of hydroelectric energy to both nations.
5. The St. Lawrence Seaway is the worlds longest seaway connecting the St. Lawrence River and the Great Lakes. Being so , the St. Lawrence helps trades between not only the USA but other countries connected to the St. Lawrence River.