Anio Vetus

Aniene
An 1886 German map of the settlements, roads, and aqueducts around ancient Rome. The Anio is the principal left-hand tributary of the Tiber, joining it just north of Rome.
Country	Italy
Basin
Main source	Filettino 1,075 m (3,527 ft)
River mouth	Tiber (Rome, ponte Salario) 41°56′30″N 12°30′07″E / 41.941745°N 12.50181°E / 41.941745; 12.50181Coordinates: 41°56′30″N 12°30′07″E / 41.941745°N 12.50181°E / 41.941745; 12.50181
Basin size	1,414 km2 (546 sq mi)
Physical characteristics
Length	99 km (62 mi)

The Aniene (pronounced [aˈnjɛːne]; Latin: Anio), formerly known as the Teverone, is a 99-kilometer (62 mi) river in Lazio, Italy. It originates in the Apennines at Trevi nel Lazio and flows westward past Subiaco, Vicovaro, and Tivoli to join the Tiber just north of Rome. It thus formed the principal valley east of ancient Rome and was an important water source as the city's population expanded. The falls at Tivoli were noted for their beauty. Historic bridges across the river include the Ponte Nomentano, Ponte Salario, and Ponte di San Francesco, all of which were originally fortified with towers.

The confluence of the Aniene and Tiber was controlled by Antemnae, a Latin settlement on a hill just to its south. Rome's foundation myths numbered them among the Sabines seized by Romulus but that his wife Hersilia convinced him to make its people Roman citizens after their defeat and annexation around 752 BC.