Cerchia dei Navigli


The Cerchia dei Navigli was the floodable defensive moat of the medieval walls of Milan, with its southeastern part transformed into a, or navigable canal. For this reason, it was also known as the Naviglio Interno, Fossa Interna, or Cerchia Interna. Measuring 6.5 km in length and 9 m in width in its navigable section, it was completely filled in accordance with the, Milan's first urban plan, starting on 16 March 1929, with works concluding the following year. The Cerchia dei Navigli, as a whole, was a ring of water encircling the medieval historic centre of Milan, hence its name.

Description

Constructed as a defensive moat starting in 1156 and transformed into a Naviglio in its southeastern part between 1387 and 1496 through canalization and expansion works commissioned by the Visconti and Sforza families, it served as the hub of the Navigli system of Milan. The only part of the Cerchia dei Navigli that remained a simple, non-navigable moat was the section towards the Sforza Castle, i.e., the northwestern stretch: its function was to supply water to the castle’s moat. The two branches of the Cerchia dei Navigli heading towards the Sforza Castle were called the Naviglio di San Gerolamo and the Naviglio Morto.
As its inflow, the Cerchia dei Navigli had the, which originated from the, while its outflows were the Naviglio Vallone, which then flowed into the, and a spillway canal that discharged any excess flow from the Cerchia dei Navigli into the. With the filling of the Cerchia dei Navigli, the Naviglio della Martesana was entirely diverted towards the : previously, the latter was merely a spillway canal for the Martesana, as most of its flow went into the Cerchia dei Navigli. The part of the Naviglio della Martesana/Naviglio di San Marco after the Cavo Redefossi, as well as the Naviglio Vallone and the Laghetto di San Marco, were filled in concurrently with the closure works of the Cerchia dei Navigli.
The term "Cerchia dei Navigli" today refers to a, whose route largely coincides with that of the Naviglio Interno. A project is currently underway aiming to restore the ancient navigable canal along the Cerchia dei Navigli road network.

History

Construction of the moat of the medieval walls in the 12th century

The origins of the medieval walls of Milan date back to 1156, when the Lombard city was at war with Frederick Barbarossa. It was Guglielmo da Guintellino, a Genoese military engineer in the service of the Milanese, who designed the works and oversaw their construction.
Guglielmo da Guintellino also created their moat, possibly expanding the ancient Roman refossum, or the second moat of the Roman walls of Milan, which ran further out than the first, skirting the four castles defending Roman Milan. The innermost Roman moat ran alongside the walls.
The Milanese city walls, the republican ones to the south and west and the Maximian extension to the north and east, were entirely made of masonry. Some significant monuments, especially churches and convents, stood outside them, and settlements and activities had developed around them.
The new ring of medieval walls was built, larger in scope, in 1156. It fully protected the city and channeled the waters of the Seveso and the into its moat. These waters were diverted into the new moat serving the walls, which were twenty-four arms wide; the excavated earth was then used to build large ramparts. Their location coincides with the modern streets of the Cerchia dei Navigli road network.
This defense system was strategically well-placed but not particularly effective, as it was built with earth reinforced by palisades and defended by wooden towers. These were the materials available to Milan, far from stone quarries and lacking elevations for fortified defenses.
Frederick Barbarossa, during the, seized it and razed the city, dispersing the Milanese to nearby villages and destroying the Roman walls, the only ones made of masonry. In 1171, as a consequence of the 1162 destruction, work began on a more effective defensive system, this time in masonry, equipped with a flooded moat also fed by the waters of the Olona, which until then had been an indirect tributary of the Roman walls’ moat and underwent its second diversion in history on this occasion.
The city had long had a complex water system: it received waters from the Seveso, Acqualunga, Molia, Nirone, Pudiga, and Olona; some entered the city, some surrounded it or exited.
Bonvesin de la Riva describes the medieval walls of Milan in his work , written in 1288:
The medieval moat, later surpassed militarily, contributed to the city’s prosperity, from trade to agriculture, as it was the regulating center of the irrigation system and the many activities made possible by flowing water: mills, fulling mills, presses, hammers, and twisting machines. Some of these activities survived even after the transformation of the ancient defensive moat into a navigable canal, which began at the end of the 14th century. The expansion work required several decades, concluding at the end of the 15th century.

Visconti-era expansion and transport of marbles for the Duomo

It was Gian Galeazzo Visconti who began major works in 1387 to make the ancient moat navigable up to the Laghetto di Santo Stefano, with the goal of transporting by water the marbles and materials essential for the Fabbrica del Duomo to build the Milan Cathedral. Until then, the only vessels navigating Milan’s canals were small barges. With the decision to allow barges carrying the Duomo’s marble blocks to pass, a problem arose: the draft of these vessels was much greater than that of the small barges that had navigated Milan’s canals until then. For this reason, the expansion and dredging of the medieval moat were necessary.
The first works undertaken were the expansion and dredging of the medieval moat from the modern via Molino delle Armi to the Ca' Granda, where, in 1388, the Laghetto di Santo Stefano was created as the docking point for materials destined for the Duomo’s construction, located 500 meters from the cathedral’s construction site. After these works, the ring of water surrounding the medieval city was called the Cerchia dei Navigli.
These works made it possible to navigate from Lake Maggiore, where the quarries, used to clad the Duomo, were located, to Milan. Specifically, vessels from Lake Maggiore entered the Ticino River, then the Naviglio Grande, and finally the Laghetto di Sant'Eustorgio, from where materials were transported, with great difficulty, overland to the Cerchia dei Navigli, where they were reloaded onto barges and continued their journey by water to dock at the Laghetto di Santo Stefano.
Regarding the navigation of Milan’s Navigli, the construction, between 1438 and 1439, of the Naviglio Vallone, which connected the Laghetto di Sant'Eustorgio to the Cerchia dei Navigli, and the, the first navigation lock built in Europe, was decisive. These eliminated the aforementioned overland transport of marbles from the Laghetto di Sant'Eustorgio to the Cerchia dei Navigli. The construction of the Conca di Viarenna was necessary to overcome the approximately two-meter elevation difference between the Cerchia dei Navigli and the Laghetto di Sant'Eustorgio. Vessels destined for the Duomo’s construction site, unlike all others navigating Milan’s Navigli, bore the inscription, which granted exemption from tolls. From "AUF" derives the idiom "a ufo," meaning "free" or "without paying." At one end of the Conca di Viarenna, a shrine, originally located on one of its sides, was reinstalled, bearing the 1497 ducal decree engraved on a Candoglia marble plaque that exempted vessels carrying materials for the Duomo’s construction from toll and duty with the formula.
Legend has it that along the northwestern Cerchia dei Navigli, the Magna, the floating palace of Filippo Maria Visconti, the last duke of this dynasty and younger son of Gian Galeazzo, traveled. The duke moved between the castles of Milan, Abbiategrasso, Cusago, and Pavia only by water, both for state affairs and to visit his many lovers. Initially, he traveled uncertain routes through ditches and canals descending to the Naviglio Grande, then, from 1445, through the Conca di Sant'Ambrogio, specially built in the current via Carducci, and the Conca di Viarenna.

Connection with the Martesana in the Sforza era

Ludovico il Moro, in 1496, completed the expansion and dredging of the Cerchia dei Navigli to the north, beyond the Laghetto di Santo Stefano, making it navigable also for barges carrying heavy goods; this part of the Cerchia dei Navigli extended to the Laghetto di San Marco, which was connected to the Naviglio di San Marco, the continuation of the Naviglio Martesana downstream of the, after which it changed its name. The Laghetto di San Marco, the Naviglio di San Marco, the Naviglio della Martesana, and the Conca delle Gabelle were built earlier, in 1469: with these works, the navigable Cerchia dei Navigli was completed. From this moment on, it was possible to navigate uninterruptedly from Lake Maggiore to Lake Como via Milan through the Naviglio della Martesana, a canal originating from the Adda River, which is itself an outflow of Lake Como.
There were also two secondary branches of the Cerchia dei Navigli, never made navigable, connected to the Sforza Castle’s moat, completing the water ring around the city to the northwest: one descended from the northern vertex of the fortification via via Pontaccio, rejoining the navigable moat, while the other, the so-called "Vercellino branch", exited from its southern vertex along via Carducci, rejoining the navigable moat at its end.
The part of the Cerchia dei Navigli starting from the modern via Carducci, the so-called Vercellino branch, was also called the Naviglio di San Gerolamo, while the other branch, starting in via Pontaccio, after the filling of the castle’s moat in the 17th century due to its diminished military importance, took the name Naviglio Morto, as it reached the fortification without an outlet.
The section of the Cerchia dei Navigli missing to complete the entire navigable ring had a different history tied to the fortification’s events, its moat, and the many transformations it underwent over the centuries. From the north, water descended via via Pontaccio and merged with water from ditches, springs, and sources flowing in the area around the current Arena Civica, encircling the castle and enriched by other sources from the northwest : it exited the castle from the southern vertex and, through the esplanade of the current Piazzale Cadorna, flowed into via Carducci, where it joined the Naviglio di San Gerolamo.
Measuring 6.5 km in length and 9 m in width in its navigable section, the Cerchia dei Navigli had, along its banks, 30 derivation outlets feeding irrigation and milling ditches. Orchards and mills were indeed present along its route. Related to this characteristic, the name of one street of the Cerchia dei Navigli is indicative: via Molino delle Armi.
As its inflow, the Cerchia dei Navigli had the Laghetto di San Marco, which originated from the Naviglio di San Marco, while its outflows were the Naviglio Vallone, which then flowed into the Darsena di Porta Ticinese, and a spillway canal that discharged any excess flow from the Cerchia dei Navigli into the Vettabbia.
The Vettabbia, in particular, originates in the street of the same name from the confluence of the Molino delle Armi canal, the Fugone del Magistrato, and the Vetra canal.
The Vetra canal, passing under the, originated from the Cerchia dei Navigli at the height of Piazza della Resistenza Partigiana and ran eastward through via Gian Giacomo Mora, via Urbano III, and Piazza Vetra, where it joined, as mentioned, the Fugone del Magistrato and the Molino delle Armi canal to form the Vettabbia.

Filling

The medieval walls were replaced by the Spanish walls of Milan, built between 1548 and 1562, while the Cerchia dei Navigli was completely filled between 1929 and 1930.
Currently, the Naviglio della Martesana reaches the bastions of Porta Nuova, where it sharply changes direction towards the southeast, becoming the. Before the filling of the Cerchia dei Navigli, the Cavo Redefossi was merely a spillway canal for the Naviglio Martesana, which discharged most of its flow into the Cerchia dei Navigli.
In the past, the Naviglio della Martesana continued its urban route, now filled at its intersection with, towards the southwest, passing Porta Nuova, crossing under the Spanish walls, then the, and finally reaching the Conca dell'Incoronata, after which it changed its name to Naviglio di San Marco. Shortly after, the latter gave rise to the Laghetto di San Marco, which flowed into the Cerchia dei Navigli through the Conca di San Marco.
The Naviglio and Laghetto di San Marco, the Naviglio Vallone, and the stretch of the Naviglio della Martesana from Porta Nuova to the Conca dell'Incoronata were completely filled concurrently with the closure works of the Cerchia dei Navigli, between 1929 and 1930.
In contrast, the Naviglio Morto and the Naviglio di San Gerolamo, the two branches of the Cerchia dei Navigli originating from the Sforza Castle, were filled earlier, between 1894 and 1895, due to hygiene issues caused by stagnant water. The Laghetto di Santo Stefano was filled for hygiene reasons, due to stagnant water, in 1857.
The first official document to discuss the filling of the Cerchia dei Navigli was the Piano Beruto, Milan’s first general urban plan, approved in 1884: it took nearly five decades for the works to begin, but once started, they proceeded quickly. The city benefited from modernization but radically changed its appearance, losing its identity as a "city of water."
From Luca Beltrami, to Riccardo Bacchelli, to Empio Malara, many commentators argued that modernization and adaptation to mobility and development needs could have been achieved without losing one of the city’s distinctive features. Alessandro Manzoni and Filippo Turati held different views, describing the Cerchia dei Navigli, respectively, as an “impure wave” and a “slimy, mottled, putrid vortex”. Stendhal, who resided in Milan for seven years in the early 19th century, described the Cerchia dei Navigli positively as “canals-boulevards,” evoking the Parisian avenues.
On 3 March 1928, permission was sought from the Ministry of Public Works, with a positive outcome, to fill the Cerchia dei Navigli and the connected canals, namely the stretch of the Naviglio della Martesana from Porta Nuova to the Conca dell'Incoronata, the Naviglio di San Marco, the Naviglio Vallone, and the Laghetto di San Marco. The decision was motivated by new traffic needs and hygiene issues caused by illegal discharges from buildings along the canals, which ended up in the Cerchia dei Navigli instead of the sewer system.
The filling of these Navigli took place between 1929 and 1930: with their disappearance, a ring of roads took their place and name: the Cerchia dei Navigli road network. With the disappearance of the watery Cerchia dei Navigli, the last water mills along its banks also vanished.
The cost to the Municipality for filling the Cerchia dei Navigli and the connected canals was over 27 million lire at the time. Marcello Visconti di Modrone, podestà of Milan, saved on improvement costs, reducing them by 18%.

Cerchia dei Navigli road network

The Cerchia dei Navigli road network, winding from the Cadorna railway station, near Piazza Castello, through via Pontaccio, San Marco, Fatebenefratelli, Piazza Cavour, Senato, San Damiano, Visconti di Modrone, Francesco Sforza, Santa Sofia, Molino delle Armi, Edmondo De Amicis, and Giosuè Carducci, returning to the Cadorna railway station, this time from the side of the namesake piazza, became Milan’s innermost ring road, although even at the time it was described as a “noose around the neck” rather than a “road ring,” due to its very short radius, which brought vehicular traffic into the city center.
In reality, the ancient navigable route did not entirely coincide with the road network but had a path that, unlike the latter, passed through Porta Nuova, crossed the Conca delle Gabelle, the Conca di San Marco, as well as the namesake laghetto and street; then it reached, at the beginning of via Fatebenefratelli, the canal that circumnavigated the city clockwise up to via De Amicis; from here, the Naviglio del Vallone curved outward and descended, through the Conca di Viarenna, to the Darsena di Porta Ticinese to reach the Naviglio Grande and Pavese.
The term "Cerchia dei Navigli" today refers to a ring of roads surrounding the center of Milan, whose route largely coincides with that of the Naviglio Interno. The area of Milan within the cerchia, corresponding to the medieval historic centre, covers 2.97 km².
The streets of modern Milan that are part of the Cerchia dei Navigli road network are:
  • via Giosuè Carducci
  • via Molino delle Armi
  • via Santa Sofia
  • via Francesco Sforza
  • via Uberto Visconti di Modrone
  • via San Damiano
  • via Senato
  • via Fatebenefratelli
  • via Pontaccio
  • via Tivoli
  • Piazza Castello

Reopening project

The Faculty of Architecture of the Politecnico di Milano conducted studies from 2008 to 2010 on the possibility of restoring the Cerchia dei Navigli and its connected canals. Professor and architect Andrea Cassone documented these studies in the publication "Riaprire i Navigli si può", published by Biblion Edizioni, Milan, 2012.
The project aims to reopen the Cerchia dei Navigli and its connected canals, restoring the ancient connection between the Naviglio Martesana, from , where this canal currently goes underground under via Melchiorre Gioia, and the Naviglio Vallone, which would again flow into the Darsena di Porta Ticinese.
This project involves the creation of a new canal, along via Melchiorre Gioia and the Cerchia dei Navigli road ring, spanning eight kilometers, mostly along the ancient riverbed, to ensure the restoration of the hydraulic continuity of Milan’s Navigli network.
The general idea of the project was presented to the public in its full complexity for the first time during the presentation of the volume "Riaprire il Naviglio si può" on 15 March 2012 in Milan, in the presence of the then-mayor Giuliano Pisapia.
The project was further illustrated in numerous public meetings, particularly during a series of conferences held on 20 October 2012 at the Teatro Puccini in Milan, titled "Riaprire i Navigli. Un grande progetto per Milano, la Lombardia e i suoi paesaggi", on 15 June 2013 at the Sala Alessi of Palazzo Marino, titled “Rifacciamo Milano con l'acqua”, and on 8 February 2014 at as part of Arnaldo Chierichetti’s exhibition, titled: "L'immagine dei Navigli tra passato e futuro".
According to the study by Biscardini and Cassone, the Naviglio della Martesana from Cassina de' Pomm should continue along via Melchiorre Gioia, cross the Bastioni di Porta Volta, and proceed towards via San Marco, Fatebenefratelli, Senato, San Damiano, Visconti di Modrone, Francesco Sforza, Santa Sofia, Molino delle Armi, Edmondo De Amicis, and Conca del Naviglio up to the Darsena di Porta Ticinese. Existing vehicular road crossings would be preserved, and additional pedestrian crossings could be created.
At regular intervals, discussions about a possible concrete reopening of the Navigli resurface: the latest proposal occurred during preparations for Expo 2015, hosted by Milan.
Regarding the reopening of the Cerchia dei Navigli and its connected canals, on 12 and 13 June 2011, Milanese citizens were called to the polls for a consultative referendum, held concurrently with four other municipal consultative referendums and the four national abrogative referendums: the outcome for the referendum on the Navigli’s restoration was overwhelmingly in favor of their reopening, with a percentage of 94.32%.
On 5 October 2017, the Milan city council resolved to organize a new consultative referendum on the reopening of the Cerchia dei Navigli and connected canals, to be held alongside the general elections of 4 March 2018, but the government did not authorize it on that date. Consequently, the city council, to avoid significant costs, decided to replace it with a public consultation on a preliminary project to open part of the route, consisting of five sections for an estimated cost of 150 million euros, postponing the rest of the reopening to a later phase for approximately 350 million euros more. The five sections, totaling 2 km out of the 7.7 km overall, are:
  • A via Melchiorre Gioia from Cascina de' Pomm to via Carissimi
  • B Conca dell'Incoronata
  • C via Francesco Sforza
  • D Piazza Vetra and via Molino delle Armi
  • E Conca di Viarenna.
They will be connected by an underground pipe to carry water to the various sections.
The consultation took place between June and September 2018 on the technical and economic feasibility project concerning the “Hydraulic Connection Naviglio Martesana – Darsena and the reopening of five sections of the Milanese Navigli,” developed by MM Spa in November 2017. The timeline envisages tendering the work in 2019 and starting construction in 2020. The project should be included in the Municipality of Milan’s Three-Year Public Works Plan attached to the 2019 preliminary budget, which the city council must approve by March 2019.