Taranto's pre-history dates back to 706 BC when it was founded as a Greek colony, established by the Spartans. The ancient city was situated on a peninsula on which the modern city has been built over the ancient Greek city of which only a few ruins remain including part of the city wall, two temple columns dating to the 6th century BC and tombs.

The islets of S. Pietro and S. Paolo (St. Peter and St. Paul), collectively known as Cheradi Islands, protect the bay, called Mar Grande (Big Sea), where the commercial port is located. Another bay, called Mar Piccolo (Little Sea), is formed by the peninsula of the old city, and has flourishing fishing. Mar Piccolo is a military port with strategic importance.

At the end of the 19th century, a channel was excavated to allow the military ships to enter Mar Piccolo harbour, and the ancient Greek city become an island connected to the mainland by bridges. In addition, the islets and the coast are strongly fortified. Because of the presence of these two bays, Taranto is also called “the city of the two seas”.