Built in the mid 1700s, the Aqueduct das Águas Livres soars 65 meters above the Alcantâra Valley. Today, the waters have stopped running, and the aqueduct has been opened to tourism. For a small fee, you can walk all the way across.
Located within the old Barbadinhos Pumping Station, the Museu da Agua introduces visitors to the once-painful process of bringing drinking water to the people of Lisbon. The museum’s highlight is its engine room, where 19th-century steam-powered pumping machines have been preserved in magnificent condition.