The Bronx is the northernmost borough of New York City, coextensive with Bronx County, in the U.S. state of New York. It shares a land border …The Bronx is the northernmost borough of New York City, coextensive with Bronx County, in the U.S. state of New York. It shares a land border with Westchester County to its north; to its south and west, the New York City borough of Manhattan is across the Harlem River; and to its south and east is the 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.