Harbors are sheltered areas where ships can safely approach the shore and anchor. The development of good harbors, both natural and artificial, was important for the international trade and the military conquests of the ancient Greeks and Romans.
Prior to about 700 B.C., the only harbors that existed were naturally protected areas that allowed workers to row small boats out and back for the loading and unloading of ships. In many areas, natural harbors such as these continued to be used until the end of ancient times. The earliest known artificially constructed Greek harbor was at Delos, an island in the center of the Aegean Sea, and the site of many great festivals attended by people from all over the Greek world. In the 700s B.C., a massive stone mole* was built to improve the harbor at Delos. It extended more than 300 yards out from the shore, assuring a safe anchorage to ships docking there. Moles were built in other harbors as well, becoming standard at most major Greek seaports by 400 B.C.
Greek harbors also featured stone docks along the shore and warehouses for storing trade goods. Harbors intended for military ships were often fortified. Towers built at the end of moles created a narrow entrance to the harbor that could be closed with chains. In addition, walls built around the port prevented attacks by land. Athens and other Greek cities constructed walls several miles long that joined the city with its harbor.
Since almost all vessels using the ports were sailing ships, some harbors provided two basins for more convenient docking, one on either side of a promontory*. These two sheltered areas, facing more or less in opposite directions, allowed sailing ships to take advantage of winds from different directions. Since maneuvering sailboats inside a narrow harbor was difficult and dangerous, tugboats towed arriving ships to dockside.
During the Hellenistic* period, the size of harbors increased, and lighthouses were added to guide ships safely to shore. The first lighthouse, built at the Egyptian port of Alexandria, was so impressive it became known as one of the Seven Wonders of the World. The lighthouse’s tower rose at least 300 feet into the air, with a blazing fire at the top that could be seen 30 miles out to sea. It was used for about 1,500 years until it was destroyed by an earthquake.
The Romans developed a construction technique that enabled them to build harbors even where the water was not naturally sheltered by land. To accomplish this, they used a type of concrete that hardened under water. About A.D. 50, the emperor Claudius launched the construction of a deep-water port at Ostia that served the city of Rome for the next 500 years. On a beach just north of the mouth of the Tiber River, engineers built two great moles of stone and concrete, creating a sheltered basin about one-third of a square mile in size. Near the end of one mole rose a massive lighthouse. Later emperors made additions to this harbor.
* mole stone or earth barrier that protects the shore from waves
* promontory high peak of land that sticks out into the water
* Hellenistic referring to the Greek-influenced culture of the Mediterranean world during the three centuries after Alexander the Great, who died in 323 B.C.
Ancient harbors were populated by people from many foreign lands. Italian and East Asian merchants, for example, worked at the Greek harbor of Delos. Harbors required many types of workers—laborers to unload and load the ships, fishermen, tugboat pilots, and clerks. Thieves and other less desirable people inhabited harbors as well. Harbors provided ancient states with substantial revenues through the collection of harbor fees and customs duties. (See also Naval Power, Greek; Naval Power, Roman; Ships and Shipbuilding; Trade, Greek; Trade, Roman; Transportation and Travel.)