Greensboro ( (); formerly Greensborough) is a city in and the county seat of Guilford County, North Carolina, United States. It is the third-most populous city in North Carolina, the 70th-most populous city in the United States, and the largest city in the Piedmont Triad metropolitan region. At the 2020 United States census, its population was 299,035. Three major interstate highways (Interstate 40, Interstate 85, and Interstate 73) in the Piedmont region of central North Carolina were built to intersect at this city.