Milan's canal system — the Navigli — represents one of the most ambitious hydraulic engineering projects of pre-industrial Europe. At its maximum extent, the network connected Milan to Lake Maggiore in the northwest, to the Ticino and Po rivers in the south, and through a series of smaller channels to quarries, forests, and agricultural land across the Lombard plain. Today, only two canals remain open for navigation: the Naviglio Grande and the Naviglio Pavese.
Origins and Early Construction
The first documented canal in the Milanese network, the Ticinello, was excavated in the late 11th or early 12th century to improve water supply to the city. The Naviglio Grande — the most significant canal in the system — was begun in 1177 and extended progressively over the following two centuries. By the mid-13th century, boats could travel from the Ticino to Milan, a distance of roughly 50 kilometres.
The primary freight justification for the Naviglio Grande was the transport of marble from the Candoglia quarries near Lake Maggiore to the construction site of Milan Cathedral (Duomo di Milano), which began in 1386. The marble blocks were loaded onto flat-bottomed barges and moved through the lake and river system, then into the canal to a dock inside the city walls. The cathedral's construction authorities held a special tax exemption on canal tolls for marble shipments, a privilege that remained formally in effect until the 20th century.
Leonardo da Vinci and the Chiuse (Locks)
The canal network's expansion in the late 15th century coincided with Leonardo da Vinci's residence in Milan under the patronage of Ludovico Sforza. Leonardo worked on hydraulic problems related to the Navigli between approximately 1482 and 1499, and his notebooks contain detailed drawings of canal engineering solutions including mitre gate lock designs.
The chiusa (lock) type attributed to Leonardo's influence — a chamber with mitre gates at each end allowing water levels to be equalised before a vessel passes — became standard in the Navigli system. The Chiusa di San Marco, near the Naviglio della Martesana, is often cited as an early example of this form in Milan, though the precise relationship between Leonardo's designs and built structures is a matter of ongoing historical discussion.
The Network at Its Peak
By the 19th century, the Milanese canal network had grown to include several principal channels:
- Naviglio Grande: connecting Milan to the Ticino at Turbigo, approximately 50 km; primary route for timber, stone, and building materials
- Naviglio Pavese: running south from Milan to Pavia, approximately 33 km; completed in its current form in 1819 under Napoleonic-era direction
- Naviglio della Martesana: running east from Milan to the Adda river at Cassano d'Adda, approximately 38 km; used for grain transport from the eastern Po plain
- Naviglio di Bereguardo: a shortcut connection between the Naviglio Grande and the Ticino, historically used for time-sensitive freight
- Naviglio Interno: the inner-city canal ring, now completely covered
At peak commercial activity in the late 19th century, hundreds of barges transited through Milan annually, carrying construction materials, agricultural produce, firewood, and manufactured goods. The tolls collected at canal gates represented a significant municipal revenue source.
Decline and Partial Closure
The railway connection between Milan and various regional centres, established progressively from the 1840s onward, began to draw freight traffic away from the canals. Road transport accelerated this process in the early 20th century.
The decision to cover the inner canal ring (Naviglio Interno) was made by the city of Milan in the 1930s, primarily for public health reasons related to flooding and sanitation. The work was carried out in stages between 1929 and 1930. The canals of the Navigli Pavese and Grande were retained as functioning waterways partly because their catchment areas were too large to cover economically and partly because some freight movement continued.
Commercial freight on the Navigli effectively ceased by the 1960s. The canals have since been managed primarily for their role in irrigation water distribution to the surrounding agricultural plain, which remains their principal operational function today.
Current Navigation Status
The Naviglio Grande and Naviglio Pavese are navigable for small recreational craft. The lock at Pavia on the Naviglio Pavese connects to the Ticino, allowing passage to the Po. Navigation is subject to seasonal water availability; summer months may see reduced levels that restrict even shallow-draft vessels.
A canal maintenance and restoration programme has been periodically discussed at the regional level, with proposals to restore the Naviglio della Martesana for navigation and to partially uncover sections of the inner canal for urban public space. Progress on these proposals has been slow due to the complexity of underground infrastructure in central Milan.
For historical documentation of the Navigli system, the Civiche Raccolte d'Arte di Milano holds architectural and engineering drawings from multiple periods of the network's development. The Museo della Scienza e della Tecnologia in Milan maintains exhibits on Leonardo's hydraulic work in the context of the canals.