• The Pont du Gard in southern FrancePont du gard image by harrybibi from Fotolia.com
  
  An aqueduct is an ancient system designed to move fresh water from a source to a town. During the Roman empire, countless aqueducts were built over hundreds of years. Whether conveying water through underground tunnels or in high, bridge-like structures, aqueducts were a major feat of Roman engineering. Remnants of these impressive structures can be seen today throughout Italy and other parts of Europe.
  
  

Aqua Appia

• The construction of the first aqueduct to bring water to Rome, the Aqua Appia, took place during the administration of Appius Claudius Caecus in approximately 317 B.C. Over 16 km long, most of of its length was underground to avoid potential poisoning from neighboring enemies. This aqueduct and the Via Appia, one of the most famous Roman military roads, were considered to be breakthroughs in engineering and construction during this era.
  
  

Aqua Marcia

• One of the longest Roman aqueducts, the Aqua Marcia was built between 144 and 140 B.C. The source for the water was over 91 km away in the Anio Valley. The water transported by the Aqua Marcia helped Rome expand into a large imperial city.
  
  

Aqueduct of Segovia

• This aqueduct, which runs through the town of Segovia in Spain, is one of the most-recognized free-standing aqueducts built during the Roman empire. Its origins are largely undocumented, but it was most likely constructed during middle to late first century A.D., after the Roman conquest of the region. The visible structure was made of large blocks and runs a length of 728 meters through the center of town. Today, the aqueduct stands as one of the prime examples of Roman architecture in modern-day Spain.
  
  

Pont du Gard

• Located in the southern areas of modern-day France, the Pont du Gard is an aqueduct built sometime during the first century A.D. After Julius Caesar's victory over the Gauls, this water system was constructed to supply the nearby city of Nimes. Though much of the water flows beneath the ground in tunnels, the most famous section is a large above-ground structure that crosses the Gard River. Today, this section is the center of a well-preserved tourist area.