The Bronx is the northernmost borough of New York City, coextensive with Bronx County, in the U.S. state of New York. It is south of Westchest…The Bronx is the northernmost borough of New York City, coextensive with Bronx County, in the U.S. state of New York. It is south of Westchester County; north and east of the New York City borough of Manhattan, across the Harlem River; and north of the New York City borough of Queens, across the East River. The Bronx, the only New York City borough not primarily located on an island, has a land area of 42 square miles and a population of 1,472,654 at the 2020 census. Of the five boroughs, it has the fourth-largest area, fourth-highest population, and third-highest population density.