Texarkana is a city in the U.S. state of Arkansas and the county seat of Miller County, on the southwest border of the state. As of the 2020 census, it had a population of 29,387. It is the twin city of Texarkana, Texas, located just across the state line. The city was founded at a railroad intersection on December 8, 1873, and was incorporated in Arkansas on August 10, 1880. Texarkana and its Texas counterpart are the principal cities of the Texarkana metropolitan area, which in 2021 was ranked 289th in the United States with a population of 147,174, according to the United States Census Bureau.

The Red River, or sometimes the Red River of the South to differentiate it from the Red River in the north of the continent, is a major river in the Southern United States. It was named for its reddish water color from passing through red-bed country in its watershed. It is known as the Red River of the South to distinguish it from the Red River of the North, which flows between Minnesota and North Dakota into the Canadian province of Manitoba. Although once a tributary of the Mississippi River, the Red River is now a tributary of the Atchafalaya River, a distributary of the Mississippi that flows separately into the Gulf of Mexico. This confluence is connected to the Mississippi River by the Old River Control Structure.