Elvas Aquaduct

One evening in 1498, when things were a little more peaceful, but the threat of siege was always on the horizon - literally - Elvas citizens hit on the plan to build an aquaduct. It took a while to complete the astonishingly enormous edifice " about 200 years with stoppages" says the guide book. It is 8 thousand metres long and brought water to the town until replaced in the mid sixties.