Rio Grande City is a city in and the county seat of Starr County, Texas. The population was 13,834 at the 2010 census. The city is 41 miles (66 km) west of McAllen. The city also holds the March record high for the United States at 108 °F (42 °C). The city is connected to Camargo, Tamaulipas, via the Rio Grande City–Camargo International Bridge. The city is situated within the Rio Grande Valley.
The area around Rio Grande City was first populated in 1846, when it served as a transfer point for supplies and soldiers supporting General Zachary Taylor's invasion of Mexico. It was a logical point for trade, as it was the highest point up the Rio Grande (known as the Rio Bravo in Mexico) for reliable steamboat traffic, and intersected a number of overland routes to Saltillo, Monterrey, and Northern Mexico.
During the early stages of the Mexican–American War, one of the soldiers stationed here, Henry Clay Davis, married Hilaria de la Garza Falcon, a resident of Camargo and heiress to the land on which Rio Grande City now sits. At the end of the war, Davis set out to organize this area into a formal city, breaking up the land into plots.