Modern Marvels

St. Lawrence Seaway (11x33)

Air date: Sep 15, 2004

The St. Lawrence Seaway is a monumental stairway in water, lifting massive ships hundreds of feet over thousands of miles. An essential part of the commercial infrastructure of the US and Canada, this complex system provides direct access from the Atlantic to North America's heartland, enabling ships packed with trade to stop at any one its 65 ports--from Montreal to Duluth.