> Which river has a Spanish name that means "big river?"And the answer: Rio Grande.Meaning "big river" in Spanish, the Rio Grande was named El Río Bravo del Norteby Spanish explorers in the 1500s, and is still known as Río Bravo in Mexico.The river starts in the Rocky Mountains and flows for nearly 1,900 miles beforereaching the Gulf of Mexico.Photo credit: ROBERT ALEXANDER / GETTY IMAGES.The Rio Grande is thefifth-longest river in the United States, and among the 20 longest in the world.The river begins as a snow-fed mountain stream some 12,000 feet above sea level,and slowly descends in elevation – across steppes and deserts – until it flowsinto the Gulf of Mexico. On its way there, the river flows along seven Americanand Mexican states: Colorado, New Mexico, Texas, Chihuahua, Coahuila, Nuevo Leónand Tamaulipas.Image credit: AmericanRivers.org.The Rio Grande has long served as a boundaryline in western expansion. In fact, the river was the physical border in disputebetween the Republic of Texas and Mexico in the 19th century. Today, it remainsthe border that divides the United States and Mexico. Despite its divisivequalities, however, the Rio Grande has also given life to a number of cities inthe southwestern United States and northern Mexico. Major cities along the RioGrande in the States include Santa Fe, Albuquerque, Las Cruces and El Paso. Onthe Mexican side, cities such as Matamoros, Ojinaga, and Ciudad Juarez allbenefit from the river's watershed. Irrigation has been practiced along theriver for millennia, dating back to the ancestors of the Pueblo Native Americansin New Mexico. Learn more about the Rio Grande below.