Sitka, Alaska, with a 2010 census population of only 8,881, but with a consolidated land area of 2,870 square miles (7,433 kilometers) is the largest city by land area in the United States of America. It is located in the southeast portion of the state on the west side of Baranof Island and the south half of Chichagof Island in the Alaskan Panhandle. The four largest cities by area in the United States are all located in Alaska, and are significantly larger than any other city in the country. The largest city by area in the contiguous United States is Jacksonville, Florida at 747 square miles (1,935 kilometers).

American cities come in all different sizes with unique environments and cultures. Cities can be expansive urban areas that cover miles of land, or dense, heavily populated metropolises.

When evaluating how "large" a city is, the population is typically used as the measurement. Cities are less commonly measured by the size of their land area. Often, the land area does not correlate with population size. For example, New York City has a 2010 census population of 8.6 million people but is 302 square miles (784 kilometers) because New York is so densely populated with approximately 27,000 per square mile.

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