Aqua Marcia was one of the longest aqueducts in ancient Rome, stretching approximately 91 kilometers (57 miles). Completed in 144 BCE, it was named after the Roman praetor Quintus Marcius Rex, who oversaw its construction. The aqueduct sourced water from springs in the Anio Valley, providing a vital supply of fresh water to the city. The structure featured impressive engineering, including arches and bridges to traverse valleys and hills. Aqua Marcia was known for its high-quality water, which was used for drinking, public baths, and fountains. It remained in use for centuries, showcasing the advanced infrastructure of ancient Roman civilization.