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 Waterway lake freighters to travel from the system's saltwater outlet to its far interior. The Waterway has larger locks and deeper drafts than the lower Seaway, limiting large freighters to the four lakes upstream of the Welland Canal and Lake Ontario and similarly restricting passage beyond the canal by larger ocean vessels. The two waterways are often jointly and simply referred to as the "St. Lawrence Seaway", since the Great Lakes, together with the St. Lawrence River, comprise a single navigable body of freshwater linking the Atlantic Ocean to the continental interior. Shipping channels separate upbound traffic from downbound traffic. The