Travis County is located in south central Texas. As of the 2020 census, the population was 1,290,188. It is the fifth-most populous county in Texas. Its county seat and most populous city is Austin, the capital of Texas. The county was established in 1840 and is named in honor of William Barret Travis, the commander of the Republic of Texas forces at the Battle of the Alamo. Travis County is part of the Austin–Round Rock–Georgetown Metropolitan Statistical Area. It is located along the Balcones Fault, the boundary between the Edwards Plateau to the west and the Blackland Prairie to the east.