In the context of our neat and predictable world, we may find attractive what defies regularity and appears to be a product of procedures with unpredictable outcomes. Walking in medieval European towns, we appreciate the geomorphic non-rectangular street grid, the warmth of the unpretentious, the constant refutation of the expected, the imperfections, and the many phases of buildings' construction and retrofitting—each of which has left visible traces.

These qualities are the very opposite of the classical ideals, namely the principals of and the more or less immovable in time order. Symmetry in Greco-Roman antiquity meant the balanced, harmonious, synthesis of distinct architectural elements; while order meant the rank in the magnitude, positioning, and succession of the elements or parts that constituted a whole—whether it was a building or the speech of an orator.

Perhaps medieval cities' only feature that corresponds fully to the classical ideals is the clarity of their boundaries in contrast to dispersed cities. We should keep in mind, though, that Hellenistic and Roman cities didn't have clearly defined boundaries either, since mansions and gymnasia, theaters and odea were often built where there was available land, namely outside the walls.

As seen, cities in ancient Mesopotamia, as well as several Greco-Roman cities developed without a preconceived plan. Their layout was the result of a rather cumulative build up. It did not follow a blueprint—but was not unreasonable or disorderly—and was the result of action by a multitude of agents and the balance of opposite forces. The inconvenience caused by building a new house or adding a new room had to be minimized by shaping it to avoid friction among neighbors, rather than according to some inflexible ideas translated into a strict comprehensive building code.

Respecting the family hearth limited the ability of central authority or the ruler to shape the city according to his/her desires—although the expropriation of property and the demolition of houses were taking place, as we have seen, at least from the Oval Temple's era. In medieval Europe, the walls defined the boundaries that constricted the expansion of the cities. The pressure to occupy the unbuilt space for housing was counterbalanced by the necessity to ensure free access to everyone and to maintain the functional width of the streets.

Throughout history, “organic growth” was often not left completely unchecked, but was delicately regulated with the enactment of appropriate legislation or through customary law. From what we know from the Roman eastern provinces of the late imperial period, for example, it was forbidden to build a new edifice in way that prevented the lighting and insolation of existing neighboring buildings. Undoubtedly such provisions—which were adopted by the Byzantine empire and helped shape the medieval European legislation—were vague enough, allowing a wide range of interpretations. Frequently, more precise provisions existed: for example, that cantilevered overhangs of newly erected buildings could not be located closer than ten feet to respective overhangs of existing neighboring buildings. In ancient Athens, such overhangs were banned altogether around 500 BCE; in medieval Rome, in 1452 CE.

“Allegory of Good Government,” Ambrogio Lorenzetti

Such provisions complemented a body of moral practices and customs that were formed over time; they regularly defined the position of a new building in relation with the existing ones and not each building's position regardless of the others in a Cartesian coordinates system. The resulting cityscape is very familiar to us because its structural logic unfolds slowly before our eyes. The buildings' sequence corresponds to our walk and is not governed by principles better understood when looking on the map. In Ambrogio Lorenzetti's frescoes (painted around 1340) in the Palazzo Pubblico (the town hall) of Siena, at a time when it was governed by the ideal city, the buildings are crammed one next to another without geometric order and discipline, but without one overshadowing the rest, some still under construction—i.e., with unknown final form yet—which makes the city a work in progress in every sense of the word.

During the centuries of Roman domination, the cities had developed administrative, financial and cultural centers whose survival depended on a sophisticated transportation and disposal network for the products from the countryside. Due to the loss of territory, the dissolution of the central authority, and the disuse of the transportation system, the cities were desolated or lost large portions of their population, who either died or relocated to the countryside in order to survive. Even in cities that retained part of their population, people turned to agriculture: the fields and pastures were now closer or adjacent to their homes, often within the city walls.

The first signs of recovery appeared a few decades before the year 1000, in some cases even earlier. Several medieval European cities inherited the street grid as it was shaped in the Roman period. In some cases, this survived almost intact—in Pavia, for example. In other cases, as in Florence, the densification of the urban fabric gradually but radically reformed it between the fourth and twelfth centuries. The fortification of the compounds of powerful families and the creation of stores and workshops narrowed or completely blocked the once straight roads and created impediments and blind alleys; the initial lack of strong administration allowed cities to be transformed into medleys of small enclaves. In some cities, the traces of their older phases disappeared almost completely. Often the ruins of monumental buildings were recycled and used as foundations for modern constructions—the Piazza Anfiteatro in Lucca is situated exactly where the Roman amphitheater's arena stood and has exactly this shape: it resulted by constructing in its perimeter, on the foundations of the seating sections, new edifices; a similar procedure transformed the Stadium of Domitian in Rome to one of the most beautiful squares of the city, the Piazza Navona.

Many European medieval cities, especially in the north, began from temporary settlements outside a religious installation, as in the case of Speyer, the Roman Nemetum, which was the seat of the local bishop. Wealth, knowledge and considerable political power were gathered there, i.e. the right conditions for business transactions: trade was the activity that contributed arguably more than any other in the creation of the first urban nuclei several hundred years after the collapse of Rome.

Compared to the countryside, the cities were another world. Slowly, from the eleventh century on, their inhabitants were organized, mainly through their closed professional associations, the guilds, into political entities, the communes. Gradually, the emerging urban economy was partially disengaged from rural production, relying also on trade and handicrafts and using money as a medium of exchange; money that could be accumulated and then invested in any enterprise considered advantageous. In this environment, the inhabitants of the cities gradually gained from the nobility and the church what we nowadays call basic human rights: the right to work and do business, the right to own property, and the right to a fair trial. Generally speaking, peasants were still deprived of these rights, since they were mostly serfs—i.e., annexed to the land where they worked. The emergence of cities significantly affected their lives as well. “Stadtluft macht frei” (urban air makes you free) is a German medieval saying, referring to a customary law that decreed that if a serf took refuge in a city and lived there for a year and a day he became free; he could no longer be reclaimed by his master and became bound to the city. This law was partially abolished in 1232 when several cities in Central Europe were fairly strengthened and threatened to bleed the great landowners dry of their available manpower. Further south, however, the situation unfolded quiet differently: in 1256, for example, as the culmination of a tendency to abandon serfdom—which was not as widespread in Italy as it was in other parts of Europe—all the serfs of the territory controlled by the city of Bologna were freed, which resulted in the immediate increase of the city's population by 5,000. In contrast to the ideal Renaissance city of the circle of Piero della Francesca, Lorenzetti's fourteenth-century ideal city is full of people— people who work, trade, display their wealth and social status. The limited public space of the medieval city, and especially the central square, was rich with activities: most of the trading activities were conducted there; the authorities made announcements and important issues of the city were discussed, something that was originally done in churches; public spectacles were presented and religious processions were organized; justice was administered and the witches were burned. The complex balance of forces within each city was manifest in its form. From early on, the competition to control its configuration was fierce: where there is high concentration of people this is worthwhile.

The church, representing a God who inspired fear and awe, was always a powerful political and cultural player, and regularly claimed the role of community leader; tellingly, the cathedrals were molded as the city's most prominent buildings. Political supremacy was often also claimed by the commune, whose relations with the church ranged from outright competition to cooperation to submission. Political bipolarity was transferred to space, with the cathedral and the city hall featuring the large square in front, regularly being the two pivotal points. The mighty were highlighting their power in various ways. In central Europe, kings and local nobility, monastic orders, and the communities themselves did so by building castles at the highest point of the city; in central and northern Italy, families with great influence and wealth, not least by building towers whose height often exceeded seventy meters, while their surface was limited to one room. Moreover, the aim of the powerful (for practical reasons and for reasons of prestige) to be close to the areas where the social, political, and financial power were concentrated resulted in the construction of the largest and tallest buildings in the city center, and the less impressive and humble structures toward the periphery.

As communities became stronger, they often tried to shape the cities in ways they believed reflected their political identity. Furthermore, in order to accomplish this, they acted drastically. In some cases, they clashed directly with nobility over the city's image, a domain that extended from aesthetics to symbolism. For instance, when the balance of power allowed it in the second half of the thirteenth century, several Italian cities enforced the reduction of the towers' height or their demolition altogether. In Florence, the maximum height for buildings was set at twenty-nine meters. In Bologna, only two of a total of nearly two hundred towers remained. Siena followed an equally harsh policy; moreover, like Florence, it usurped the symbols that the nobles had used up to that point to highlight their power: it built a town hall with a tall slender tower. In San Gimignano, a city only a few kilometers away from Siena, fourteen of the about seventy medieval tall towers have survived and still dominate the skyline of the city.

The management of the city's image was used by the most vibrant communities as tool for enhancing collectivity. Conceiving of the city in its entirety as a work of art, and not merely focusing its attention on monumental buildings, each commune elaborated a series of measures aimed at harnessing individual initiative to serve the common purpose: the creation of an aesthetically sound and orderly city.

Siena probably attempted this more systematically than any other city. On the one hand, gauging how the care for public spaces was indicative of its priorities, the community assigned the cleaning of the roads to the adjacent owners and introduced fines for offenders. On the other hand, it embarked on the endeavor to homogenize the form of the city: firstly, by imposing a monopoly on the bricks, i.e., the basic building material, a move primarily designed to generate great revenue; and secondly, by introducing a body of building regulations. These measures were explicitly stated to aim at the city's beauty and the satisfaction of all its inhabitants; their result was that the new buildings that gradually replaced the old—especially in the most central parts of the city—had many more common features between them, than the buildings depicted in Lorenzetti's ideal city. In it, the traces of the past were still vivid, especially in the form of tall slender family towers, which would eventually cease to excite the imagination of the inhabitants of the Italian cities in the fourteenth, and especially in the fifteenth century when a new paradigm for the houses of the powerful emerged in the form of the Renaissance's palazzi.

The width of the streets of Siena was set at approximately six-anda-half meters for the main arteries and at three meters for the secondary streets. And it was determined that “any edifices that are to be made anew anywhere along the public thoroughfares … proceed in line with the existent buildings and one building [shall] not stand out beyond another, but they shall be disposed and arranged equally.”3 Particularly strict regulations applied to the rebuilding of mansions in the main square, despite them housing some of the city's most powerful families. These, then, were to be uniform; their windows were to be shaped like those of the city hall and balconies were banned. Located next to each other, their façades formed one large surface embracing the town hall, placed at the lower part of the square, which spread amphitheatrically before it. Paved with red bricks forming nine circle sectors, the square commemorated the community's governance by the Nine.

The town hall, which began around 1300, has three wings: the central wing is somewhat reminiscent of the town hall in Florence, Siena's eternal rival in Tuscany, which in turn seems to have been inspired by the domiciles of the powerful of the era; the two lateral wings are lower and positioned at an angle to the central wing so that the town hall's façade is gently incurving, giving the impression that it is an organic part of the square. The references to the mainstream at the time—the crenellations and the tall slender tower, all useless remnants of the past— abound.

The town hall is thus integrated into a whole comprised of both the public and private buildings as primum inter pares, the first among equal buildings of the city. In stark contrast to the town hall stands the cathedral, which dominates the city on a hilltop 200 meters away. Its construction began about eighty years before the construction of the town hall. Over one hundred meters long, richly decorated, and with the colors of the Sienese coat of arms, the cathedral markedly stands out from all the secular buildings of the city: such a great straight line as the cathedral's axis does not exist anywhere else in the city, nor does such an elaborate and consistent decoration.

More than in Italy, Gothic architecture in Central and Northern Europe contributed to making the cathedrals the exceptional structures they are. The early features of the new architecture, which swept across the continent and the British Isles within a few decades, date back at least to the eleven-thirties, when Abbot Suger—a close associate of French kings Louis VI and Louis VII—set out to rebuild the basilica of Saint Denis to ease congestion and to flood it with light.

With immense height, the delicate, graceful Gothic cathedrals absorbed a great part of the local population's wealth and energy for generations. It seems that in erecting them, people saw the opportunity to transcend the rather harsh reality they faced in their everyday lives and to partake in the quasi virtual world of amazing edifices they themselves created, and which they more or less perceived as constructs made possible through divine intervention. They inspired others to follow suit and create similar wonders in their towns.

The extremely impressive appearance of the Gothic cathedrals is due, clearly, to their daring static taking full advantage of the stone's strength, which is stressed to its extreme—even subjected to tension, where applicable. But this is also due to their display of a high degree of regularity combined with extreme visual complexity. The drawings of Villard de Honnecourt—a monk from Picardy who lived in the middle of the thirteenth century—preserved in a folder with thirty-three parchment sheets, clearly demonstrate this characteristic trait of Gothic architecture: people's faces and Gothic buildings' ornamentations, worked in detail, are organized according to simple geometric principles. The blend of elementary geometry with visual intricacy is present in buildings across the globe: in Chapter 9, we saw that this was the case with Angkor, too. This alone would suffice to make Gothic cathedrals distinctive from the edifices that surrounded them, and were distinguished for the opposite qualities: for the irregularity of their outline, combined with rich variation in texture and the lack of finely worked details.

Walking in Siena today, we appreciate not so much its order and homogeneity—the declared objectives of its leaders, especially during the administration of the Nine—but, again, for the irregularity that we perceive in it. Our judgment is not completely arbitrary; those who regulated and controlled the building activity in the thirteenth and fourteenth centuries envisioned a regularity that was not in the same league with what was sought after and realized the following centuries (and we are now accustomed to). On the one hand, they had in front of them the strictly regular cathedral of their city; on the other hand, the pandemonium of the small, private buildings with walls that stooped from the passage of time, the openings at irregular intervals, columns, arches, and windows rarely uniform, the repeated additions and extensions. They followed a middle path and attempted to give the city a unified appearance, relating the distinct parts that comprised it to each other. It was an appearance that did not result from detailed planning, but was not shaped without principles. It was based on relative positioning and not on geometric patterns, on gradual evolution and not on predetermined schemes, on balance and not on repetition, on ingenuity and not on a model; a form, which in our eyes balances between regularity and irregularity.

This occurred neither for the first nor for the last time in history. The great Greek temples of Asia Minor of the sixth century BCE are typical of such balance: their columns (all the same height, needless to say) were very different from each other, prepared by different workshops, which had great freedom of choice. Next to each other, the columns formed the colonnades supporting the epistyles and the friezes. No one could argue that in sixth-century BCE Ionia, the sense of individuality was more advanced than in Pericles' Athens when the Parthenon was built, where the columns—also made from different workshops—have the slightest possible differences between them.

With the construction of the huge Gothic cathedrals, and the increasing regulation of the city form, a major shift in people' s perception became apparent of the line that separates diversity from chaos, unimaginative severity from order, and dry repetition from homogeneity; perception that never ceased to shift in time.