The aqueduct was constructed in quite recent times, rain-water having previously given the only supply.
An ancient aqueduct is built into the eastern side of the wall.
Trajan built an aqueduct which can still be traced.
In the vicinity are the remains of a Roman aqueduct, which formerly spanned the valley.
It contains few remains of antiquity, except of the aqueduct and basin, said to have been made by the architect Eupalinus for the tyrant Theagenes.