Buffalo is the second largest city in the U.S. state of New York and the largest city in Western New York. 's census estimates, the population was 256,322. The city is the county seat of Erie County and serves as a major gateway for commerce and travel across the Canadian border, forming part of the bi-national Buffalo Niagara Region and Buffalo–Niagara Falls metropolitan area. As of 2010, the Buffalo–Niagara Falls metropolitan area had a population of 1,135,509; the combined statistical area, which adds Cattaraugus County, had a population of 1,215,826 inhabitants.