ancient seaport of Mauretania, located west of what is now Algiers in Algeria. Iol was originally founded as a Carthaginian trading station, but it was later renamed Caesarea and became the capital of Mauretania in 25 BC. The city was famous as a centre of Hellenistic culture, and under the Romans it became one of the most important ports on the African coast.

The modern town of Cherchell is a small fishing port, occupying a much smaller area than did the ancient settlement.