Alcântara Valley, Lisbon
Construction started in 1731 and, although the project was still unfinished, the aqueduct finally brought water to the city in 1748. The main course of the aqueduct covers 18 km, but the whole network of canals extends through nearly 58 km. A total of 35 arches cross the valley, covering 941 m (the tallest arches reach a height of 65 m.).
The aqueduct survived the 1755 Great Earthquake with no damage and it worked until 1967.