City  — Flag Seal Nickname(s): Space City (official), more. . . City of Houston Location in the United States of America Coordinates: 29°45′46″N 95°22′59″W / 29.76278°N 95.38306°W / 29.76278; -95.38306Coordinates: 29°45′46″N 95°22′59″W / 29.76278°N 95.38306°W / 29.76278; -95.38306 Country United States of America State Texas Counties Harris, Fort Bend, and Montgomery Incorporated June 5, 1837 Government  - Type Mayor–council  - Mayor Annise Parker Area  - City 601.3 sq mi (1,558 km2)  - Land 579.4 sq mi (1,501 km2)  - Water 22.3 sq mi (57.7 km2) Elevation 43 ft (13 m) Population (2010 US Census)  - City 2,100,017 (4th U.S.)  - Density 3,897/sq mi (1,505/km2)  - Urban 3,822,509 (10th U.S.)  - Metro 6,108,060 (6th U.S.)  - Demonym Houstonian Time zone CST (UTC-6)  - Summer (DST) CDT (UTC-5) Area code(s) 713, 281, 832 FIPS code 48-35000 GNIS feature ID 1380948 Website houstontx.gov Houston (pronounced /ˈhjuːstən/) is the fourth-largest city in the United States and the largest city in the state of Texas. According to the 2010 U.S. Census, the city had a population of 2.1 million people within an area of 579 square miles (1,500 km2). Houston is the seat of Harris County and the economic center of the Houston–Sugar Land–Baytown metropolitan area—the fifth-largest metropolitan area in the U.S. with a population of approximately 6.1 million..