The Aniene River is a tributary of the Tiber River in central Italy. It flows for about 99 kilometers, originating in the Simbruini Mountains and passing through the Lazio region. The river is known for its clear waters and scenic landscapes, making it a popular spot for outdoor activities like hiking and fishing. Historically, the Aniene River has played a significant role in the development of nearby towns, including Tivoli and Subiaco. The river's waters were harnessed for ancient aqueducts, contributing to the water supply of Rome. Today, it remains an important natural resource in the region.