Converging on the horizon at the city of Caesarea, the high-level aqueduct and the low level aqueduct appear as scars in the golden Mediterranean sand north of the ancient port. The high-level aqueduct is the prominent straight line to the right; it was probably first built by Herod when he founded Caesarea and then later enlarged by Hadrian in the second century to double its capacity. The water that flowed in the 6 ½ mile long high-level aqueduct came from springs deep in the flank of Mt. Carmel, over 12 miles from the city. The spring water was first carried for 6 miles through a rock-hewn tunnel within the mountain, it then flowed into the high-level aqueduct to continue its journey to Caesarea.
To the left of the high-level aqueduct is the fainter line of the much shorter low level aqueduct. This fifth century A.D. addition to Caesarea’s water supply system brought less pure water to the city from a river 4 ½ miles north of Caesarea. The water carrying capacity of the high and low level aqueducts together indicates that in the fifth century, when both aqueducts were used, the demand for water of an enlarged Caesarea was five times the city’s need in the second century.