Today Port Suez is a modern city with three harbors on the Red Sea, but in the 25th century B.C.E., it was the site where the pharaohs protected their lands from marine invasions. From Port Suez, the Suez Canal flows 193 kilometers (120 miles) through the Isthmus of Suez, across saline lakes known as the Bitter Lakes, to Port Said on the Mediterranean Sea. Built under the guidance of French diplomat Ferdinand de Lesseps, the canal took 10 years to construct, opening in 1869. It's noteworthy for its narrow width—which means that large ships need to travel single file and wait for each other to pass—and the fact that it has no locks, so water flows through from one sea to the other. When the Suez Canal opened, it eliminated the need for ships to sail around Africa to reach South Asia: It reduced the journey by 7,000 kilometers (4,350 miles).