Weslaco is a city in Hidalgo County, Texas, United States. As of the 2010 census the population was 35,670, and in 2019 the estimated population was 41,629. It is located at the southern tip of Texas in the Rio Grande Valley near the Mexican border, across the Rio Grande from the city of Nuevo Progreso, Rio Bravo, Tamaulipas.
Weslaco derives its name from the W.E. Stewart Land Company. It was the hometown of Harlon Block, one of the Marines photographed raising the flag at Iwo Jima, and of film and television actor David Spielberg.
