The water supply to the city of Lisbon was a problem that lasted centuries. Successive solutions were outpaced by demand from the inhabitants that never stopped increasing. From the 1880s onwards, the Alviela River, with its source in Alcanena, became the capital's main drinking water supplier.

The distance between the source of the river and the city of Lisbon is around a hundred kilometres. To transport the water gravitically, a gigantic aqueduct with this length was built between the river source and the city. In some places, the aqueduct is underground; in others, it is superficial. When it needs to cross a valley, it rises above arches, like this one, the Louriceira Aqueduct, of which I present this image.

Built in limestone, the water flows inside a closed channel at the top of the aqueduct. On a beautiful late afternoon a few days ago, with a completely clear sky, I saw a full moon rising between the aqueduct's arches, a scenario I tried to capture with a Hasselblad H4D. The sensor has a maximum ISO 800, so I used a 4-second exposure and several LED spotlights to illuminate the aqueduct.