The aqueduct usually called that of Valens was actually completed in 368 during the reign of this emperor, but certainly planned and begun already in the time of Constantine the Great (died 337) or his son Constantius. Of this monument, a great part is still preserved, but appears much lower than in the byzantine time, since the surrounding ground level has risen up to 6 m. The aqueduct transported water, that came from two different supply systems, over the little valley between the fourth and third hill of the city. It ended in a great reservoir in the vicinity of the Forum of Theodosius. The aqueduct was in use throughout the byzantine and most of the ottoman time.