Leonardo's Urban Plans (Research Essay)

Milan! Today it is one of Italy’s most modern cities with skyscrapers, cars, and subways. Back in 1482 when Leonardo arrived in town it was a crowded medieval town that lacked sanitation. The town would be hit by the bubonic plague soon after his arrival, killing 50,000, or 1/3 of the city at the time. This plague and the unsanitary conditions Leonardo experienced in Milan would be the inspiration for his urban designs.

Most of Leonardo’s urban designs are kept today in the form of dozens of sketches enshrined in a few of his notebooks. Leonardo’s plans were vastly different from his predecessors. He focused very little on the aesthetic designs and did not illustrate a full layout of the city, nor did he demark the location of churches or other buildings, only some houses. Essentially, his plans were only seen in a series of snapshots of the city. He also sometimes did birds eye views of the city, again ignoring magnificent buildings of Rome depicted by others of his time. After taking a modern urban planning course at Purdue and after doing master planning at my internship last summer, I would be hard pressed to call any of these designs a complete urban plan. They are more of preliminary sketches and concept art for a city, but not complete plans. The sketches honestly remind me a lot of my recent research: they are preliminary sketches trying to get the idea out there but are not fully thought out with several sketches contradicting each other.

Benefits of Leonardo’s designs and the interesting things he did:

Leonardo’s snapshots allowed him to include elevations of the buildings (although he ignored most details of the buildings, he was particular about the heights), and this allowed him to showcase his most interesting design aspect. His designs indicated a multi-layered city. On the first level was a street to handle commercial traffic and on the upper level was a street to handle pedestrian and “gentleman” traffic. This idea was amazing at the time and is honestly even amazing today. Only a few cities have layered streets like this: including Chicago in the Loop area. His idea of having underground corridors to move traffic live on in Milan with the subway system there. The idea of layering traffic to increase capacity and to separate loud traffic from pedestrians is a very modern idea.

Another idea that he had that is incredibly modern is the idea that the street width and the heights of the buildings on the street should have a 1-to-1 ratio. This is one of the key points of New Urbanism. The ratio between the height and width of a public space as one of the fundamental ideas of the profession in modern times with limits on setbacks, maximum heights and road widths all defined in zoning codes. Now Leonardo was arguing to increase street widths and decrease density, while modern planners are arguing that our streets are too wide and to decrease the street width and increase density, but they seem to agree on this idea of a 1-to-1 ratio.

Another modern idea he had was inclining the street in the middle to move waste off the street. As you may know, any paved road designed today has a curve in the middle to move waste, so Leonardo was towards a modern track there.

Leonardo also suggested a grid with wide, straight streets. This is obviously very familiar to us in modern times and is very different from the nearly random streets of medieval times. This grid also is representative of Roman urban planning (which Leonardo probably derived the idea from), as can be seen in Florence’s almost grid south of el Duomo set by the Romans.

Leonardo also had a slight form of zoning, and even redlining, both modern zoning. He did this vertically by segregating the poor to the lower streets and had commercial deliveries to the lower streets while shop owners lived above (this idea is more medieval than modern, but the separation of classes in the city’s design was more modern).

He also worried about flood control and tried to use canals to place his ideal city away from the river. A bit different from modern techniques but zoning empty land and using dams were not common practices back then and he had the right idea to think of a solution.

By far the biggest modern focus that Leonardo focused on was sanitation. He placed canals in a grid throughout his city to transport poo away, designed ventilated bathrooms, ventilated the rich’s room and placed their rooms as high as possible, designed spiral staircases between the lower and upper streets to discourage public urination, and placed underground tunnels and canals (although these didn’t carry waste in many of his designs, but rather were for delivery of goods). He based the canals after his work in Milan’s canals, using the same widths and the canals acted as his sewage system. This was truly innovative, as prior to now waste removal was done residence by residence and typically just for the rich. He anticipated the modern-day need for a system of waste management. Leonardo was quite obsessed with this idea of sanitation and everything else discussed about his urban plans revolves around this idea of sanitation and moving the poo away. It is quite clear what inspired this: the bubonic plague that killed off 1/3 of Milan right in front of Leonardo’s eyes.

Issues with Leonardo’s designs:

Sterner argues that waste should be used for productivity as it was in Medieval times. He argues that it should be fuel for agriculture instead of just washed away as da Vinci would have it. He says we are wasting waste, but medieval cities before da Vinci used their waste. Simply pushing the waste away is certainly inefficient, but it is better than having it sitting in the street.

The real issues with Leonardo’s plans are that they are not actually plans and are full of discrepancies and logical fallacies and are more theoretical than practical, especially given our modern knowledge.

There are consistent instance of drawings and descriptions not matching. That spiral staircase mentioned earlier is not in any of his drawings, but a ramp is in one of them. The underground canals are present in some drawings, but in other drawings he makes no use of the tunnels and moves the canals to the streets. Drawings are also poorly labeled. One drawing has labels for a, b, c, d, e, and f but no explanation as to what these are. This indicates to me that these sketches were more just ideas and are to work individually or that he changed his mind on some of these ideas over time.

The other major issue is the consistent logical fallacies and non-sequiturs. He placed two tunnels under the house, one for waste and one for commercial traffic, but these tunnels would have to be too large to fit under the house and for the house to have support given the techniques at the time. It also is illogical to have that many tunnels in the city at the time. The architecture of the houses was unconvincing, leaving loggias in the back with no view and cramped mezzanines. His two-level street design also fails. He wants commercial traffic to go on the lower street, but some of his drawings have the city surrounded by a moat or have canals crisscrossing it. The only way into the city is the upper road and there is no easy way to get commercial traffic to the lower levels except stairs, which wont work for the heavy carts. He also wanted waste to flow to the lower streets in most of his drawings, but not the tunnels below, but there is debate if he really meant this. The tunnels are clearly more effective than just dumping waste on another streets. His canal layout was not very efficient for water flow and using canals to simply move waste is not effective (sewer pipes is a much better use of space and are less likely to clog full of waste). Overall, he had good ideas, but the details needed to be worked on and he was very inconsistent with his plans.

Leonardo’s did do one city deign for a real-life city. He was hired to design a palace in Romorantan, France, which ended up being more of a small town. He used many of the ideas described above, such as wide streets and a grid pattern, as well as a focus on sanitation. His design was never actually built, but some say his use of sanitation inspired the French king he designed the palace for to enact the Hygiene Edict of 1539, mandating the removal of waste from the city and setting a modern standard of waste removal. This is probably Leonardo’s most lasting impact on urban planning: bringing sanitation back to cities.

Deeper Analysis in the Transition

There is a definite difference in culture seen in the transition through Leonardo of medieval to modern urban planning. Modern urban plan see urban planning as an economic value- designing cities to increase property values of the residents and to improve the safety and overall wellbeing of residents. Wellbeing typically means just overall health and safety of residents, but more postmodern urban planning like New Urbanism advocate for qualities of life beyond health and safety of residents and argues for things and making an aesthetically pleasing city that promotes walking, environmentally friendly design, mixed zoning and housing, and good aesthetics. There is also this idea of being efficient with resources, such as what Sterner suggests (which is interesting pulling from the medieval mindset of using everything available). The good aesthetics goes back to medieval "planning," which mostly just focused on placing palaces and churches in good locations. The planning revolved more on where the church was, or the common-man's access to God. The streets were laid out based on how people moved, the shape of the land, and just wherever the building is placed. There were also more thoughts on defenses, like walls and moats, both to protect against invasion and to unite the people within and separate them from the people outside. There was little focus on movement, and more focus on place and a logic focusing on the area itself. Leonardo moves towards modern planning by shifting focus towards efficient movement of people, zoning different occupations and separating traffic, and especially by focusing on health and sanitation to improve safety. I referred several times in this analysis to Leonardo's work not being a full plan in the modern sense, and I stand by this assessment. He was certainly closer to modern day urban planners, who would see medieval planning as a joke that lacks any focus on movement and speed, but he also lacked the full implementation and analysis that grew in the 1900s with the advent of the car and the high density of cities. Modern urban planning includes traffic analysis, and tries to decrease the delays experienced by users and focuses entirely on moving people as quickly as possible by building large highways and big interchanges, even destroying the places people are supposed to be going to in the process. Many American cities tore down whole neighborhoods and bulldozed large sections of the downtown to create faster avenues of transport and for room to store these vehicles (cars). For these cities, "a thing's place was no longer anything but a point in its movement" (Foucault 23). Urban planning is now looking back on itself and asking if it can improve, with some even suggesting melding new technologies into the urban landscape through smart cities. There is also some backlash on the focus on movement, with a suggest to rebuild places and make the street not an avenue for movement- but a destination as is the case in the Strong Towns movement and an argument against stroads and car infrastructure being made central to our cities. Post-modern planning looks to shift focus from being only about movement to recreating the places that the renaissance thought overlooked and reconnecting to the human element instead of treating the city like a machine that needs to be efficient. The future moves on, and it is clear that Leonardo was a part of this transition to modern urban planning, especially given his shift to focus on movement in the city.

The idea of what we call city planning, or what was called utopias in medieval times and city design in postmodern times has changed. In medieval times, the focus was on the buildings themselves and on making these buildings pleasing to God. There was less focus on function, but a focus on place. Leonardo and modern planners shifted focus to making cities more efficient in moving people, goods, and waste and not on place. This is a throwback to Roman planning, with its straight, gridded streets, and focus on an efficient city and aqueducts to move water.  Leonardo keeps some forms of utopia by making his designs not birds eye views like modern plans, but as snapshots of the city’s buildings. Postmodern planning, especially with the publishing of the book “The Life and Death of Great American Cities” by Jane Jacobs in 1963, has led back to some calls to medieval planning by focusing on place and not how to move people there. They also do not have birds eye view of the city but focus on buildings and forms and how architecture interacts with the urban space. The most recent movements in the field have called out the mistakes of modern and renaissance planning and seek to look back an era, just as Leonardo did 400 years earlier.

Plan of Milan from Birdseye view.

Multi-layered streets

Works Cited

Clarke, Hilary. “Leonardo the City Planner: Da Vinci's New Milan.” RSS, The Institution of Engineering and Technology, 22 May 2019, https://eandt.theiet.org/content/articles/2019/05/leonardo-the-city-planner-da-vinci-s-new-milan/. 

Foucault, Michel. "Of Other Spaces." Diacritics 16.1 (1986): 22-27.

Marani, Pierro C, and Maria Teresa Fiorio, editors. Leonardo DaVinci: The Design of the World. PalazzoReale. 

Sterner, Carl S. “Waste and City Form: Reconsidering the Medieval Strategy.” Journal of Green Building, vol. 3, no. 3, 2008, pp. 67–78., https://doi.org/10.3992/jgb.3.3.67.