The Saint 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 Saint 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 such as grain, iron ore, and coal. The seaway consists of several key components, including the Welland Canal and various locks that raise and lower vessels to 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.