Agua Prieta is a Mexican city located in the northeast of the state of Sonora, on the border with the United States of America. The city is the municipal seat and the most inhabited locality of the Municipality of Agua Prieta. According to data from the Population and Housing Census conducted in 2015 by the National Institute of Statistics and Geography, Agua Prieta has a population of 82 918 inhabitants, which makes it the eighth most populated city in this state. Its foundation was in 1899, recognizing itself as a city from 1942. The name comes from the word ópata bachicuy, meaning 'black waters'.
This is because in the place, the water with which the farmers of the late nineteenth century, watering their cattle became dark, due to the nature of the land. It is located 4.3 km from the US city of Douglas, Arizona and 380.2 km from the state capital, Hermosillo.