Technology
The ancient Romans also had a complex system of aqueducts, which were used to transport water across long distances. The first Roman aqueduct was built in 312 BCE. The eleventh and final ancient Roman aqueduct was built in 226 CE. Put together, the Roman aqueducts extended over 450 kilometers, but less than seventy kilometers of this was above ground and supported by arches.
History of Athens
He built the first aqueduct as an underground tunnel. Its sources were most likely on the slopes of Mount Hymettos and along the Ilissos river. It supplied, among other structures, the fountain house in the southeast corner of the Agora, but it had a number of branches. In the 4th century BC it was replaced by a system of terracotta pipes in a stone-built underground channel, sometimes called the Hymettos aqueduct; many sections had round, oval or square access holes on top of about .
Pipe segments of this system are displayed at the Evangelismos and Syntagma Metro stations.