Great Lakes nations maintain coast guard vessels in the Great Lakes. During settlement, the Great Lakes and its rivers were the only practical means of moving people and freight. Barges from middle North America were able to reach the Atlantic Ocean from the Great Lakes when the Welland canal opened in 1824 and the later Erie Canal opened in 1825. By 1848, with the opening of the Illinois and Michigan Canal at Chicago, direct access to the Mississippi River was possible from the lakes. With these two canals an all-inland water route was provided between New York City and New Orleans. The
Great Lakes shipping from January to March. Some icebreakers ply the lakes, keeping the shipping lanes open through other periods of ice on the lakes. The Great Lakes are also connected by the Chicago Sanitary and Ship Canal to the Gulf of Mexico by way of the Illinois River (from the Chicago River) and the Mississippi River. An alternate track is via the Illinois River (from Chicago), to the Mississippi, up the Ohio, and then through the Tennessee–Tombigbee Waterway (a combination of a series of rivers and lakes and canals), to Mobile Bay and the Gulf of Mexico. Commercial tug-and-barge traffic on