Houston is the most populous city in the U.S. state of Texas, fourth most populous city in the United States, most populous city in the Southern United States, as well as the sixth most populous in North America, with an estimated 2018 population of 2,325,502. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the seat of Harris County and 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 the Dallas-Fort Worth metroplex, with a population of 6,997,384 in 2018.