how many counties make up the rio grande valley
Rio Grande Valley The Rio Grande Valley is an area located in the southernmost tip of South Texas. It lies along the northern bank of the Rio Grande river, which separates Mexico from the United States. The four-county region, consisting of Hidalgo, Cameron, Willacy, and Starr counties, is one of the fastest growing places in the United States.[citation needed] From having about 325,000 people in 1969, to today a population over 1,300,000 in 2014. Some of the biggest cities in the region are: Brownsville, Harlingen, Weslaco, Pharr, McAllen, Edinburg, Mission, Hidalgo, and Rio Grande City.