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G - 13 : When Nature Changes the Course of History - The Silting of Ports

Last year, when sailing along the Anatolian coast, we came across many ancient harbors which are now completely landlocked. Nearby rivers carry so much sediments that the coast line is rapidly advancing. Troy, Ephesus and Miletus were just the most prominent ones. This year’s sailing route takes us to ports which were lucky enough to never have had the problem. Savona, Monaco, Antibes, Toulon and Marseille look the same as they did 2’500 years ago, when they were founded.

How Rome's Portus Augusti looked in 1582 by Ignazio Danti (Vatican Library)

The Western Mediterranean is not any different though. Upon closer look you find many silted bays which once harbored thriving ports. It is just that weather pattern, sea currents and geography play out differently. There are three major rivers which are powerful silters: the Tiber in Rome, the Arno which flows through Florence and Pisa and the Rhone with his magnificent delta. But smaller rivers also create silting problems. The silting of these ports coincided with the collapse of the Roman Empire and the end of long-distance trading.

Portus Augusti is just south of Fiumicino Airport - the Hexangon Port still intact - the orange Lines are ancient Sea Breakers, the dot to the left the ancient Light House

The silting in Ostia is probably the most prominent case albeit seldom mentioned. The Roman harbor was a magnificent piece of engineering and its remain can be seen when landing at Rome's international airport in Fiumicino. The hexagonal artificial harbor where every year 300’000 tons of wheat arrived is easily visible. The departure terminal is situated just north of it. It is kind of funny that the silting created the flat landscape that now accommodates another port – albeit a port for air planes.

Oldest Reconstruction of the Portus Augusti by Pirro Ligorio from 1554

The next example is Pisa which we today perceive as a river town. Dome and the famous Leaning Tower though were standing on the waters edge once. Pisa’s port was just to the west of the old town. It remained open to the early Middle Age during which time Pisa was a powerful sea power – at par with Genoa. But after the battle of Meloria in 1284, when Genoa destroyed its fleet and killed most of its men, Pisa seized to be a major port It did not have the funds anymore to clear the silting and is now 8 km away from shore.

Pisa in the 11th Century. The Cathedral is just north of Palos Autiuli, the old Port

With no major river nearby, Genoa and Savona never had the problem but Fréjus did. Most people are puzzled when I tell them that Forum Julii was once Rome’s major harbor in the Western Mediterranean and that a significant part of its war fleet was stationed here. Visited the town a few days ago. It is almost impossible to conceive that this was once a major port.

The Roman Light House is now surrounded by greens Fields and 4 km off the shore

The light tower which stood at the port entrance is isolated and almost disappears in the lush green. The old harbor is a green field in the middle of the town. Wonder whether the field is still very soggy – residential homes were built on all sides but the field remains. Was also looking for the giant naval base which supported the roman fleet but found nothing.

The giant Roman Naval Base to the SW of Fréjus has all but disappeared

Further to the west lies Saint Tropez which does not seem to have silting issues. But this is more due to its location at the SE tip of the bay. The Giscle river flowing into the bay is a powerful silter. Over the centuries, the coast line advanced considerably. I guess in about 2’000 years, the luxury yachts will not being able to harbor in Saint Tropez any longer. The port may be a giant parking lot. But maybe the super-wealthy will own space ships by then which would take care of their problem.

Old Map of the Gulf of Grimat with Saint Tropez at the Center. The Giscle to the right

Toulon, Cassis and Marseille have no large river in their vicinity thus do not suffer from silting. The Mediterranean current carries the Rhone river’s sediments west. We won’t sail along the Rhone delta on our way to the Baleares to avoid the risk of being caught in a powerful summer mistral. The stormy wind is even more unpleasant than the Meltemi we sailed into by bad luck in 2017 on our way from the Peloponnese to Bodrum in Turkey.

There are two towns we would have visited though: Aigues-Mortes and Narbonne. Both of them lost their access to the sea. Aigues-Mortes due to the sediments from the Rhone. Narbonne to the silt from the ancient Atax river.

Aigues-Mortes is now 4 kilometres inland - it was once France's only Mediterranean Port

Aigues-Mortes was France’s only Mediterranean port when its eastern border was the Rhone river. As the town lost its access to the sea, it fell into a beauty sleep. For centuries it kept its medieval structure and is today a major tourist magnet. Visitors come to discover how people lived 800 years ago. Aigues-Mortes was the departing port for Louis IX's seventh crusade which ended in disaster. His army was defeated and he himself ransomed for a lot of money.

Map of French King Louis IX crusade to Egypt where the Mamluks defeated his army

Narbonne had a similar fate. Once the provincial capital of the Roman Province Gallia Narbonnensis, it had a very large port. The remains, large piers, were excavated a few years ago near Castelou and give us a good picture of the thriving trade that took place in this part of the Med.

The Bay of Narbo today - the Coast Line was 2 km further inland

The harbor is a few miles south of Narbonne. During the Middle Ages, Narbonne was an important location for Occitan, France and Spain. It was built with the stones from Roman buildings. The port never recovered though. Narbonne lost its function as trading hub.

View over the large Bay of Narbo today - 2'000 Years ago it was filled with Sails

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