Herod's Amazing Port at Caesarea

The port's construction at Caesarea was an unprecedented challenge—there was no artificial harbor of this size anywhere in the world. But Herod wasn’t one to avoid a challenge and spent 12 years, from 22 to 10 BC, building a port for the luxury-goods trade (including spices, textiles, and precious stones) that would make Caesarea the economic capital of the country and the most modern harbor in the whole Roman Empire.

During underwater research in the 1970s, archaeologists were stunned to discover concrete blocks near the breakwater offshore, indicating the sophisticated use of hydraulic concrete (which hardens underwater).

Historians knew that the Romans had developed such techniques, but before the discoveries at Caesarea, they never knew hydraulic concrete to have been used on such a massive scale. The main ingredient in the concrete, volcanic ash, was probably imported from Italy's Mount Vesuvius, as were the wooden forms. Teams of professional divers actually did much of the trickiest work, laying the foundations hundreds of yards offshore.

Once finished, two massive breakwaters—one stretching west and then north from the Citadel restaurant some 1,800 feet and the other 600 feet long, both now submerged—sheltered an area of about 3½ acres from the waves and tides.

Two towers, each mounted by three colossal statues, marked the entrance to the port; and although neither the towers nor the statues have been found, a tiny medal bearing their image was discovered in the first underwater excavations here in 1960. The finished harbor also contained the dominating temple to Emperor Augustus and cavernous storage facilities along the shore.