Introduction

Bologna is a thriving city in northern Italy that has a rich history. Some cities make an effort to make their history more visible underneath modern additions. In contrast, Bologna’s medieval heritage sticks out like two, very sore thumbs. The Two Towers (Due Torri) of Bologna are vestiges of medieval conflict among the city’s rich families.
Origin and medieval history

The history of Bologna goes back to ancient times. In the 9th century BC, the Villanovan culture settled the area, and introduced iron-work. This culture developed over time into the Etruscan civilization. In the 6th century BC, they built a city named Felsina on the site.
Later in the 4th century BC, a Gallic tribe named the Boii conquered what is now northeastern Italy. This included the city of Felsina. The Romans in turn conquered the area in the 2nd century BC. They renamed the city into Bonōnia. With this name, we have the birth of Bologna as we can recognize it.
Hard times
With the decline of the Roman Empire, Bonōnia experienced many attacks from the Goths. This was in part because it served as a Byzantine stronghold in Italy. In these times of crisis, the patron saint of Bologna, Bishop Petronius, rebuilt the town. In addition, he founded the Basilica of Saint Stephen.

In the following centuries, northern Italy and Bologna fell under Charlemange and Frankish (Holy Roman) rule. In this time, the city provided a robust education of laws.
Beacon of self-determination

In the 1183 Peace of Constance, Bologna earned independence as a commune. The background is that a late emperor gave Bologna more autonomy upon his death. His successor had other ideas. In response, Bologna joined the Lombard League and defeated the Holy Roman armies.
With newfound independence, Bologna thrived as a commercial urban center. In 1088, it established the oldest continuous university in the world, the University of Bologna. It kicked off as an esteemed provider of education in medieval Roman law and medicine.
Ruin from without & within

However, this peace and prosperity didn’t last through the 13th century. Firstly, external political crises beset Bologna from without. Secondly, the elite families of Bologna fought for control within. Both worked to ruin the town. Later, Bologna became a signoria in governance.
In this chaos, the Pope spread his influence via Cardinal Bertrand du Pouget. Bologna’s well-being became far worse with the arrival of the Black Death. The following decades saw Bologna’s independence wax and wane as a result of its messy internal and external politics.
In 1506, Pope Julius II excommunicated the ruling signoria family, and put Bologna under “interdict” (exclusion from church rites). It’s in this dark period of church and state that our towers of focus rise to the sky.
Jealous beginnings

The 2 towers are named after the noble families who paid for their construction. The taller tower is named Asinelli, while the shorter and leaning tower is named Garisendi. It’s possible that aristocrats built towers in Bologna and other cities as a form of competition. The taller the tower, the more power the family had.
So many more

These towers aren’t the only ones which can still be seen in Bologna. In medieval times, there could’ve been anywhere from 80 to 180 towers. The higher count is not as probable. The number is still astounding if we consider the fact that medieval Bologna’s skyline was still fairly dense with towers.
The first person to attempt a count of the medieval towers was Count Giovanni Gozzadini. Count Gozzadini was a 19th century senator of the Italian kingdom. His thoughts were that bringing light to the history of the city’s medieval skyscrapers would bring prestige to it in the new Italian kingdom.
To this end, he also excavated ancient Etruscan and Villanovan artifacts. The Count used real estate deeds to estimate the number of medieval towers.
Remaining Few
Count Gozzadini’s estimate is where the estimated number of 180 comes from. It’s possible that he misinterpreted the documents which recorded ownership changes over the towers. For instance, it’s possible that Count Gozadini didn’t account for multiple family names used for a single tower. Over time, it seems different families took up different towers and added their own histories to the physical structures.
When scholars account for these kinds of factors, the estimated number of medieval towers at their peak goes down to between 80 and 100 in Bologna. This number is still extraordinary in light of medieval architecture, engineering technology, and the preexisting density of Bologna’s infrastructure.
Nowadays, there are almost 20 left in different conditions. They are named the Azzoguidi/Altabella, Prendiparte/Coronata, Scappi, Uguzzoni, Guidozagni, Galluzzi, and the Due Torri: Asinelli and Garisenda Towers.
Medieval construction

The towers were militant in nature. They complemented the no longer existing 12th century city walls. Aristocratic families built them with attention to a combination of practical defense and visual prestige.

Serfs were used in the construction of these towers between 3 and 10 years of labor for a 60m tower. Foundations of selenite stone were built 5 to 10 m below ground. Reinforcing poles ran through these foundations. They made the walls of the tower thinner with greater height.
In addition, the architects designed the towers to have a thick inner wall and a thin outer wall. They filled the gap between with crushed stones and mortar. Holes made in the outer walls and bases for scaffold support remain on the sides of the towers to this day.
These kinds of towers weren’t unique to Bologna. Nevertheless, these two examples give us a good start to understanding the patterns of tower construction and usage in medieval Italy.
Asinelli Tower


Garisendi Tower

This tower was originally 60 m tall. Over time, it began to lean as a result of weak foundation ground. In the 14th century, Bologna officials lowered it to the modern height of 48 m. The tower changed owners until, in the 19th century, it became municipal property.
The Florentine poet Dante Alighieri referenced this specific tower at least twice in his work Divine Comedy, like so:
As when one sees the tower called Garisenda
from underneath its leaning side, and then a cloud
passes over and it seems to lean the more,
thus did Antaeus seem to my fixed gaze
as I watched him bend…
— Divine Comedy, Inferno, XXXI, 136-140[1]
Never can my eyes make amends to me –short
of going blind– for their great fault,
that they gazed at the Garisenda tower
with its fine view, and –confound them!–
missed her, the worthiest of those
who are talked about.
— Rime, VIII[2]
Later History
Medieval repurposing
Creative applications
Modern Times


Tourism
Visitors climb the 498 steps of the Asinelli Tower for €5. There is a local superstition that those who climb all the way to the top will be unsuccessful with bad luck in their academic studies. It could be the other way around too. I certainly felt unsuccessful as I struggled to give this article more and more words towards the top of the word count tower.
Cultural Significance in Anthropology
Plenty of people compare the skyline of medieval Bologna to modern Manhattan. Let’s see what insight we can garner from this comparison. We may be tempted to reduce the construction of such towers as these in any place and time, like “dick-contests”. However, modern times show that far more can be going on behind the scenes than simply building tall and thin.
It’s also about building small. Various laws throughout the 20th century mandated restrictions on Manhattan’s skyscrapers. Some forced newer buildings to have setbacks above certain intervals of floors for the sake of greater sunlight penetration onto the streets. Others mandated that a building could stand upon a certain portion of its allotted ground area, for similar reasons as before, in addition to others.
Past skyscraper design

Many of NYC’s most famous skyscrapers were built with clever maneuvers within and around these zoning laws. The Empire State is regarded as a successful incorporation of legal restrictions into the building’s iconic appearance. Its large setbacks near the base allow for the building to become the world’s tallest upon its completion.
There’ve been numerous instances of complaints about how tall towers rise in Manhattan, while having the potential to gentrify neighborhoods at the risk of their local residents. Some examples include all the “pencil towers” of Billionaire’s Row, 200 Amsterdam, and Spitzer Enterprises’ glass apartments near Williamsburg Bridge.
Zoning loopholes

Many of these towers are built through loopholes in construction laws. One way the heights of new buildings are restricted is through enforcing a certain floor area – ground area ratio. In other words, the total floor area of a skyscraper cannot exceed the legal ratio it has with its ground area.
However, storage spaces used to contain mechanical equipment do not count as floor area. Therefore, clever architects increase the amount of mechanical space in order to reserve legal floor area for additional floors, and consequently, much taller buildings.

In addition, most of them aren’t commercial or beneficial to the community in any way. They are part-time condominium towers for international oligarchs.
Pencil towers

One of the most prominent examples of this is the 432 Park Avenue condominium in midtown Manhattan. The bands of yellow floors lighting up at night are the mechanical spaces which were used to reserve floor area for higher, additional floors. When 432 Park Avenu stood as a complete building, it exceeded the roof height of the new 1 WTC building, and that of the old North Tower.
Keep on rising

We can expect many more such buildings to rise in Manhattan’s skyline. Many of the towers along Bilionaire’s Row were likely built with similar schemes in mind. Taller, thinner towers are definitely in mind. Wind vortices and structural instability might mitigate the rise of these towers. But until then, the complaints of residents down on the ground about shadows and obstructed lives went unheard.

Never underestimate the smarts behind a “dick contest”. Rather than dismiss it, we might wonder at the craze, planning, and force which made the towers of Bologna all rise as they did in the 13th century like the towers of Billionaire’s Row rise today.