Portus

Many visitors landing at Rome's Fiumicino Airport will notice a peculiarly hexagonal lake just outside it. If it looks manmade, that's because it is: the Lago Traiano was originally carved out for Rome's main port. Although that is no longer the case, the ruins of the overlooked and appropriately named Portus have been excavated and are today open to the public.

Portus was first constructed by Emperor Claudius as a deepwater maritime port, replacing the nearby and today more well-known river port of Ostia. It was meant not only to create enough capacity to serve 1-million-strong Roman metropolis, but it was also meant to symbolize Rome's unprecedented control over the entire Mediterranean. The port's construction was quite a feat for the time, digging out a nearly 500-acre and 20-foot-deep basin out of sand dunes. The lake seen today was a second, equally ambitious basin constructed by Emperor Trajan.

Although Portus supplanted Ostia as Rome's primary port for a time, its importance ended as it silted up and Rome as a city declined. The area became a private estate, which passed into the hands of the Sforza Cesarini family, who eventually turned it into a wildlife oasis. Despite its remarkability, Portus has received less attention from archaeologists than Ostia, and consequently only a small portion of its huge area has been excavated. However, more research has been done in recent years, which hopefully will continue to reveal new insights into Roman trade and shipping.