The Red River, or sometimes the Red River of the South, 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 one of several rivers with that name. 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. The south bank of the Red River formed part of the US–Mexico border from the Adams–Onís Treaty (in force 1821) until the Texas Annexation and the Treaty of Guadalupe Hidalgo. The Red River is the second-largest river basin in the southern Great Plains. It rises in two branches in the Texas Panhandle and flows east, where it serves as the border between the states of Texas and Oklahoma. It then forms a short border between Texas and Arkansas before entering Arkansas, turning south near Fulton and flowing into Louisiana, where it feeds the Atchafalaya River. The total length of the river is 1,360 miles (2,190 km), with a mean flow of over 57,000 cubic feet per second (1,600 m3/s) at the mouth.

Lawton is a city in, and the county seat of, Comanche County, in the U.S. state of Oklahoma. Located in southwestern Oklahoma, approximately 87 mi (140 km) southwest of Oklahoma City, it is the principal city of the Lawton, Oklahoma, metropolitan statistical area. According to the 2010 census, Lawton's population was 96,867, making it the fifth-largest city in the state, and the largest in Western Oklahoma.Developed on former reservation lands of the Kiowa, Comanche, and Apache Indians, Lawton was founded by European Americans on 6 August 1901. It was named after Major General Henry Ware Lawton, who served in the Civil War, where he earned the Medal of Honor, and was killed in action in the Philippine–American War. Lawton's landscape is typical of the Great Plains, with flat topography and gently rolling hills, while the area north of the city is marked by the Wichita Mountains. The city's proximity to the Fort Sill Military Reservation, formerly the base of the Apache territory before statehood, gave Lawton economic and population stability throughout the 20th century.Although Lawton's economy is still largely dependent on Fort Sill, it has grown to encompass manufacturing, higher education, health care, and retail. The city has a council-manager government; the city council members are elected from single-member districts and the mayor is elected at-large. They hire a professional city manager to direct daily operations. Interstate 44 and three major United States highways serve the city, while Lawton-Fort Sill Regional Airport connects Lawton by air. Recreation can be found at the city's many parks, lakes, museums, and festivals. Notable residents of the city include many musical and literary artists, as well as several professional athletes.

Duncan is a city and county seat of Stephens County, Oklahoma, United States. The population was 22,310 at the 2020 census. Its main claim to fame is as the birthplace of the Halliburton Corporation. Erle P. Halliburton established the New Method Oil Well Cementing Company in 1919. Halliburton maintains seven different complexes in Duncan plus an employee recreational park, but the corporate offices relocated first to Dallas and later to Houston. Centrally located in Stephens County, Duncan became the county seat after Oklahoma achieved statehood in 1907. Oil wells opened in Stephens County in 1918 and led to rapid development. Cotton was a dominant crop until the Dust Bowl brought its decline, but cattle remains an important part of the economy. The Chisholm Trail passed to the east of Duncan prior to the town's founding, which is home to the Chisholm Trail Heritage Center.

Graham is a city in north-central Texas. It is the county seat and largest city of Young County, and as of the 2010 Census, had a population of 8,903.