Fodor's Expert Review Aqueduto da Amoreira
The 8-km (5-mile) Amoreira Aqueduct took more than a century to build and is still in use today. It was started in 1498 under the direction of one of the era's great architects, Francisco de Arruda—who also designed the Aqueduto da Água da Prata north of Évora. The first drops of water didn't flow into the town fountain until 1622. Some parts of the impressive structure have five stories of arches; the total number of arches is 843. The aqueduct is best viewed from outside the city walls, on the road from Lisbon.