The Silver Water Aqueduct (Aqueduto da Água de Prata) is the Roman aqueduct that brought water to Évora — built in the 1st century CE and still carrying water until the 20th century, a remarkable 1,900-year working life. The surviving sections run for several kilometres, entering the city from the northwest and threading through the urban fabric in ways that give you an immediate sense of how the city grew around it.
The most dramatic section is where the arches pass through residential streets in the northern part of the old town: houses have been built into the arches, balconies hang over them, and washing dries between the piers. It is a genuinely unusual urban landscape. Follow the Rua do Cano — "Street of the Pipe" — through this section for the best views of the integration between Roman infrastructure and later centuries of city building.