Houston  is the most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the seat and largest city of Harris County; as well as the principal city of the Greater Houston metropolitan area, which is the fifth-most populous metropolitan statistical area in the United States and the second-most populous in Texas after Dallas–Fort Worth. With a population of 2,302,878 in 2022, Houston is the fourth-most populous city in the United States. Houston is the southeast anchor of the greater megaregion known as the Texas Triangle.

Comprising a land area of 640.4 square miles (1,659 km²), Houston is the ninth-most expansive city in the United States (including consolidated city-counties). It is the largest city in the United States by total area whose government is not consolidated with a county, parish, or borough. Though primarily in Harris County, small portions of the city extend into Fort Bend and Montgomery counties, bordering other principal communities of Greater Houston such as Sugar Land and The Woodlands.