How is it possible that Pisa was one of the 4 maritime republics if it is not on the sea?

Venice, Genoa, Pisa And Amalfi. We all studied at school 4 maritime republicsthat is, 4 Italian cities which, especially during the Middle Ages (particularly between the 11th and 14th centuries) and at alternate periods, they entered into competition for the control of trade routes in the Mediterranean Sea and have established real commercial empires within the Mare Nostrum.

Beyond that among the maritime republics one could add other cities of the period, such as Gaeta, Ancona or Noli, today we focus on a particular question: if we observe Pisa on a geographical map, we see that it is a city without a sea, finding itself about ten kilometers away from the coast. How is it possible, then, that central Tuscany has become such an important maritime republic?

Because Pisa no longer has the sea

The explanation is scientific: hundreds of years ago coast line of today's Tuscany was not the same as today and Pisa was much closer to the sea than it is now. Today the historic center is about ten kilometers from the coast, but in Etruscan and Roman times, however, the city was right overlooking the Tyrrhenian Sea. How is it possible?

It all depends on two rivers at whose mouth the city was born: the Serchio and above all theArno. These two rivers, over time, continued to transport sand, pebbles and other types of debris downstream; this mix gradually accumulated near the mouth of the two rivers and alongside their course (in case of floods and overflows), creating new land and making the coastline advance towards the sea. It's a process called sedimentation.

Arno Pisa
The Arno river

There are no archaeological traces or documents that certify with certainty the exact conformation of the coast and its evolution in the past, especially the most ancient one, but it is known that already in III-II century BC. the ancient nucleus of today's Pisa had at least one port. At the time the town was born near the sea at the mouth of the Arno and Serchio rivers, an area inhabited by people who practiced fishing since the 9th century BC.

At that time the two mouths were not yet well defined and opened onto a wide gulf. Then, over the centuries, sedimentation has progressively given rise to alagoon and marshy areadifferentiating the mouths of the two watercourses and creating the alluvial plain where today we find the city of Pisa located.

The alluvial plain of Pisa (source: Google Earth Studio)

Brief history of the port of Pisa

They developed in the lagoon area of ​​the ancient city of Pisa various landing places and moorings, initially directly on the sea and then, as the coast line advanced, along the course of the Serchio and Arno rivers. The main ancient landing places (from the Etruscan-Roman era) were probably three: the port of the Conche (north of the city), the port of San Piero a Grado (originally at the mouth of the Arno and today identifiable in the area of ​​the basilica of San Piero a Grado) and the so-called Portus Pisanus.

It was exactly the Portus Pisanus (the last one built and modified over time) to determine the success of Pisa as maritime republic in the Middle Ages. In this period the Tuscan city was now in the hinterland and therefore its port system was very complex. The main structures and buildings (including a pier, piers and towers) are located a few kilometers from the city, on the coast, and the goods that arrived there were then transported inland along the Arno, the Serchio and thanks to a large system of canals and smaller waterways, connected to each other and to other water basins. The products not only reached Pisa, but could even be transported by smaller boats up to Lucca.

Pisa's commercial empire
Pisa's commercial empire in the Mediterranean (author: –kayac–)

The economic success which Pisa obtained thanks to the port and the trade it allowed the city to fortify port facilities further and to improve them, as well as to put in place a continuous maintenance work to prevent the port from silting up.

This development, however, led the city to enter into strong competition with other urban centers with a maritime vocation and, in particular, with Genoa. The two republics clashed in 1284 in the famous naval battle of Meloria and Pisa suffered the worst: as a consequence its port came destroyed shortly thereafter by its Ligurian rivals.

The Battle of Meloria, 1284

Although Pisa later managed to rebuild the Pisan Port, in the meantime Genoa had acquired a dominant position in the Tyrrhenian Sea and Florence was expanding inland. Maintenance works they became increasingly rare, also due to further attacks suffered by the structures. The reduced commercial revenues did not allow investments and so the city slowly let its port die which ended up partially silting up and becoming aunusable marshy areareclaimed only in the 19th century.

Marina of Pisa
Marina di Pisa, at the mouth of the Arno