The Anio River is a river located in central Italy, flowing through the Lazio region. It originates from the Simbruini Mountains and travels approximately 100 kilometers before joining the Tiber River near Rome. The river is known for its clear waters and picturesque landscapes, making it a popular spot for outdoor activities. Historically, the Anio River was significant for the ancient Romans, who utilized its waters for aqueducts, including the famous Aqua Anio Vetus. The river also played a role in supplying water to the city of Rome, contributing to its growth and development over the centuries.