What river does Lake Ontario drain into?

Lake Ontario drains into the Saint Lawrence River, which serves as a critical outlet for the lake. The Saint Lawrence River is a significant waterway that flows northeast from Lake Ontario, eventually leading to the Gulf of Saint Lawrence. This river not only facilitates the movement of water away from the Great Lakes system but also plays a vital role in international shipping and commerce, connecting the Great Lakes to the Atlantic Ocean. Through this connection, it helps regulate the water levels and contributes to the overall hydrology of the region. The understanding of this drainage system is essential for anyone engaging in activities around Lake Ontario, such as navigation, fishing, or environmental conservation.