History of New York City (1784–1854) surged far beyond its rivals, reaching a population of 1,080,000 in 1860, compared to 566,000 in Philadelphia, 212,000 in Baltimore and 178,000 in Boston. Historian Robert Albion identifies four aggressive moves by New York entrepreneurs and politicians that helped it jump to the top of American cities. Of greatest importance, it sponsored the Erie Canal which began operations in 1825, forming a continuous water route from New York north to Albany via the Hudson River, then west to Buffalo using the new canal to reach the Great Lakes. It opened a large new market in upstate New York and 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