The St. Lawrence Seaway is a system of locks, canals, and channels that allows ships to travel from the Atlantic Ocean to the Great Lakes in North America. It connects the St. Lawrence River to the Great Lakes, facilitating international trade and transportation. The seaway was officially opened in 1959 and is a vital route for shipping goods like grain, iron ore, and coal. The seaway is approximately 2,300 miles long and includes several key components, such as the Welland Canal and various locks that help ships navigate changes in elevation. It plays a crucial role in the economy of both Canada and the United States, supporting industries and providing access to inland markets.