Pecos is the largest city in and the county seat of Reeves County, Texas, United States. It is situated in the river valley on the west bank of the Pecos River at the eastern edge of the Chihuahuan Desert and the Trans-Pecos region of west Texas and near the southern border of New Mexico. The population was 9,501 at the 2000 census. The city is a regional commercial center for ranching, oil and gas production and agriculture. The city is most recognized for its association with the local cultivation of cantaloupes. Pecos claims to be the site of the world's first rodeo on July 4, 1883.