Rionegro is a city and municipality in Antioquia Department, Colombia, located in the subregion of Eastern Antioquia. The official name of the city is "Ciudad Santiago de Arma de Rionegro". Rio Negro means "Black River" in Spanish, as the city received its name after a river that looks black because of the shadows cast by trees. The river traverses the city and it is the most prominent geographical feature of the municipality. Rionegro is also sometimes called the Cuna de la democracia as it was one of the most important cities during the era of the Colombia's struggle for independence and the 1863 constitution was written in the city.