A national monument, Lisbon’s massive aqueduct was a remarkable feat of hydraulic engineering when it was built between 1731 and 1799 to supply the city with water. Spanning some 36 miles, it boasts 109 stone arches, the most dramatic of which are the 35 that cross the Alcântara Valley—they survived the 1755 earthquake remarkably intact. Tour the aqueduct, then head to the Príncipe Real neighborhood, where the Mãe d’Água das Amoreiras reservoir now functions as a museum. You can also stop for some wine at Chafariz do Vinho, a wine bar built inside the aqueduct system.

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