“A great civilization is not conquered from without until it has destroyed itself from within.”
– Ariel Durant, The Story of Civilization
The Roman Aqueduct de Santa Clara was built in 16th century to carry water from Povoa de Varzim to the Santa Clara Convent in Vila do Conde (about 30 km north of Porto). The aqueduct included 999 arches stretching for 4 km.
The first Roman aqueducts were built around 312 BC, and were a remarkable feat of engineering for that time.
The Romans also invented grid based cities, sewers and sanitation, roads and highways, surgery tools and techniques, concrete and arches, and my favorite – bound books.