Sulphur Springs is a city in, and the county seat of, Hopkins County, Texas, United States. As of the 2010 census, its population was 15,449. Sulphur Springs is located along the western edge of Northeast Texas.

Jefferson is a city in Marion County in Northeastern Texas, United States. The population was 2,106 at the 2010 census, and 2,533 as of 2018's census estimates. It is the county seat of Marion County, Texas, and is situated in East Texas. The city is a tourist destination, with popular attractions including: Jay Gould's Railroad car, the Sterne Fountain, Jefferson Carnegie Library, Excelsior House, the House of the Four Seasons, and the bayous formed by Big Cypress Bayou located in and around the city.

Longview is the 47th largest city in the state of Texas. The city is mostly located in Gregg County, of which it is the county seat; a small part of Longview extends into the western part of neighboring Harrison County. Longview is located in East Texas, where Interstate 20 and U.S. Highways 80 and 259 converge just north of the Sabine River. According to the 2010 U.S. census, the city had a population of 80,455. The estimated population in 2019 was 81,653. Longview is the principal city of the Longview Metropolitan Statistical Area, comprising Gregg, Upshur, and Rusk Counties. The population of the metropolitan area as of 2017 census estimates is 217,481.Longview was established in 1870 in what was at the time southern Upshur County. The town incorporated in 1871. After Gregg County was created in 1873, Longview was voted the county seat. Today, Longview is considered a major hub city for the region, as is the nearby city of Tyler. In 2014, Forbes magazine ranked Longview as the sixth fastest-growing small city in the United States. Companies with significant presence in Longview are Eastman Chemical, Trinity Rail Group, AAON Coil Products and Komatsu Mining. Colleges and universities in the area include LeTourneau University, Kilgore College and the University of Texas at Tyler's Longview University Center.

The Texas Highland Lakes is a chain of six fresh water reservoirs in Central Texas formed by six dams on the lower Colorado River. The Texas Colorado River winds southeast from West Texas to Matagorda Bay and the Gulf of Mexico. The dams and lakes are (from northwest to southeast, upstream to downstream): Buchanan Dam — Lake Buchanan Inks Dam — Inks Lake Wirtz Dam — Lake LBJ Max Starcke Dam — Lake Marble Falls Mansfield Dam — Lake Travis Tom Miller Dam — Lake AustinThe lower Colorado River basin has a history of major flooding. The Lower Colorado River Authority built the dams to manage floods and generate hydroelectric power in the 1930s and 1940s. The two largest lakes—Buchanan and Travis—are the reservoirs that store water supply for the region. The smaller lakes—Inks, LBJ, Marble Falls and Austin—are pass-through lakes that are operated within a certain range.