When architecture is not enough

A comparison of San Basilio and Corviale

The end of the Second World War revealed the severe housing crisis Italy was about to face, as well as the urgent need for a comprehensive rethink of urban centers. In Rome, still governed by the 1931 General Regulatory Plan, the lack of a suitable urban planning framework to guide the city’s expansion had resulted in neighborhoods and buildings devoid of urban coherence and architectural or constructional quality—often the by-products of land speculation by a handful of large landowners. From the outset of Mario Fiorentino’s (1918–1982) career, attention to the city—the “new” city—and to the role of architecture in designing residential neighborhoods for social housing became a central focus.

Fiorentino was deeply engaged in debates surrounding the relationship between architecture and urban planning, as well as in policies aimed at curbing Rome’s uncontrolled expansion. Throughout his career, he maintained a strong commitment to the issue of housing, designing numerous residential buildings ranging from individual houses to apartment blocks and entire neighborhoods for social and affordable housing.

This essay examines two of Fiorentino’s projects in Rome, which, despite their differing architectural languages and building typologies, share similar design intentions and, paradoxically, similarly unsuccessful outcomes. On one hand, there is the San Basilio UNRRA-Casas neighborhood, designed between 1951 and 1955 with Serena Boselli, located on the far north-eastern outskirts of Rome. Here, the foundational concept was rooted in the “neighborhood unit”, with buildings arranged to create small internal courtyards intended to foster community life. On the other hand, there is the IACP residential complex in Corviale, the iconic kilometere-long building in the south-western quadrant of the city, a symbol of large-scale architecture, designed and built by Fiorentino between 1972 and 1981.

Despite the twenty-year gap between the two projects and their differences in urban context and architectural approach, both were conceived to avoid social marginalization and foster community integration. However, while the ghettoization of these spaces is often attributed to their architectural typologies and layouts, this essay aims to examine the two projects in parallel—from the neorealist “small houses” to the megastructure—reflecting on the role of architecture in processes of urban isolation and analyzing the synergies necessary to build a cohesive city. Comparing these two “architectural opposites”, which nonetheless led to similar social outcomes, provides an opportunity to reflect on the insufficiency of architecture alone in addressing the challenges of contemporary urban design.

The end of World War II highlighted the severe housing crisis facing Italian cities and the urgent need for a comprehensive rethinking of urban centers. In Rome, in particular, the migration from rural areas to the city (with the population increasing from 209,222 in 1871 to 916,858 in 1931 and 2,155,093 in 1961)¹ and the destruction caused by the war exacerbated an already existing housing crisis that had begun in the early 20th century. This made the provision of new housing and the spatial reorganization of residential units more urgent than ever.

According to the 1951 census, 6.6% of dwellings were shacks, caves, or under-stair spaces; 21.9% of families lived in shared accommodations. The state housing agency INA-Casa, established by the Fanfani Law on February 28, 1949, played a key role in addressing this issue. Unlike ICP and INCIS, INA-Casa was financially robust and capable of initiating large-scale housing policies. By 1949, INA-Casa began operations, and by the following year, the first houses under the Fanfani plan appeared on the outskirts of Rome. In ten years, INA-Casa built 110,953 rooms in Rome, which by December 31, 1959, accounted for 7.33% of the total habitable rooms in the city².

Public entities responsible for economic and social housing became laboratories for architectural experimentation, shaping the form of the suburbs and leading to significant interventions across the country. These efforts reflected various architectural movements and theories over more than two decades, from the immediate post-war period to the mid-1970s.

Mario Fiorentino (fig. 1) emerged in this context. Born into a well-off Jewish family on June 5, 1918, in Rome, he lived there all his life. A contemporary of Bruno Zevi, he attended Liceo Torquato Tasso with him, and they often collaborated over the years. In 1937, Fiorentino enrolled in the Faculty of Architecture at Rome's La Sapienza University. In December 1944, after experiencing events unrelated to architecture but significant for his generation – anti-fascist struggles at the university, war, survival, resistance, political imprisonment, and liberation – he graduated with a project for a Modern Art Gallery. 

In the immediate post-war years, Fiorentino gained international recognition with the project for the Monumento ai caduti delle Fosse Ardeatine (1945-1949), created with collaborators Nello Aprile, Cino Calcaprina, Aldo Cardelli, and Francesco Coccia, alongside Giuseppe Perugini and Mirko Basaldella, the latter two authors of another project that shared the first prize in the second-degree competition. Simultaneously, between 1945 and 1946, Fiorentino worked on the Manuale dell’architetto promoted by Gustavo Colonnetti, Biagio Bongioannini, Pierluigi Nervi, Mario Ridolfi - his first mentor - and Zevi, and published in 1946 under the auspices of CNR-USIS³. He participated in the Executive Committee and the general editing of the volume under Ridolfi's guidance⁴.

Throughout his professional life, which ended with his sudden death in 1982, Fiorentino's interests, goals, and architectural principles remained consistent, focusing on three main themes: attention to urban development, particularly in Rome and its suburbs; continuous research on the use of prefabricated elements; and a clear preference for residential architecture. He often reflected on the significance of the word “home”, connecting it to his personal experiences and works, from the small neorealist houses he designed for Cutro and San Basilio to the "machine for living" that is Corviale.

This essay aims to compare two of Fiorentino's architectural experiences in Rome, differing in architectural language and building typology but sharing the same design intentions and, paradoxically, similar unsuccessful outcomes: the UNRRA-Casas San Basilio neighborhood and the IACP residential complex in Corviale. The former represents the neorealist "neighborhood unit", while the latter is a heavily criticized emblem of megastructures resulting from large-scale urban planning theories.

Situated between Via Tiburtina and Via Nomentana, the San Basilio neighborhood was designed by Mario Fiorentino in collaboration with Serena Boselli between 1951 and 1955⁵. The land, approximately 80,000 square meters in size, was granted free of charge by the Municipality of Rome. The UNRRA-Casas program provided specific guidelines for the number and type of dwellings to be allocated to homeless Roman families:

180 housing units, 10 of which with shops, plus essential services. [...] A prevalence of terraced houses with two to three bedrooms; and a building type composed of four flats, two per floor. Each dwelling had to have completely independent access and a garden plot of approximately 150–200 square metres. All buildings were to be no more than two storeys high, so as to guarantee the independence of each family unit⁶.

The site plan of San Basilio is geometric, clear and functional, “organized” along a cruciform road system that defines four residential blocks, offset from the main traffic flows (fig. 2). At the intersection of the two main roads lies the service center, comprising shops, a social welfare building, and a nursery school – all designed by Boselli. The north–south axis, intended for through traffic, was conceived in relation to the construction of the Grande Raccordo Anulare; the east–west axis connects the four residential nuclei with the surrounding districts. Each block includes an internal road system and a network of pedestrian paths that allow residents to move from one nucleus to another with minimal vehicular interference.

At the core of the scheme was still the idea of the “neighborhood unit”, with the residential volumes arranged to form small, articulated inner courtyards designed to foster community life. There is a clear reference to traditional local building practices, with masonry structures, pitched roofs, and Roman-style clay roof tiles. To lend character and visual variety to the built environment, Fiorentino employed a polychromatic palette: facades were painted in ochre, yellow, violet and light blue, with white trims around the windows and edges. Window frames were white, shutters painted green-grey, and metalwork finished in black (fig. 3-4).

As Federico Gorio noted:

The passion for studying details, the attempt to draw on a traditional, and at times even vernacular, architectural vocabulary (as seen in the corner and roof junction solutions), the effort to vary the repeated housing types to spare residents the humiliation of living in cookie-cutter dwellings — all of these are clear signs of a constant and genuine commitment that characterises Fiorentino’s urban work: to imbue state-funded housing with the warmth of human presence, and the voice of a personal relationship that rescues it from indifference⁷.

Given the tight construction schedule and limited budget, Fiorentino paid particular attention to standardizing the building components and outdoor elements, aiming to optimize site operations — an ambition that ultimately went unrealized. Fiorentino himself later described the two core issues that undermined the project during construction: first, the site was divided between two contractors, each with their own construction methods and habits, thus thwarting any attempt at standardization and industrialization; second, there was a lack of coordination in the execution of primary infrastructure works (roads, drainage, water, electricity, gas, etc.). This led to repeated demolitions of completed works (such as paving and drainage systems), continual patch-ups and modifications, which not only compromised timelines and costs, but also altered the original architectural design.

The experience of the San Basilio site served as a lesson for future projects. Notably, in the case of a complex structure like Corviale, all construction phases would later be assigned to a single contractor, and the structural system would be executed entirely using standardized components.

Nearly twenty years later, in 1972, Fiorentino was appointed one of the five lead architects -alongside Federico Gorio, Piero Maria Lugli, Giulio Sterbini, and Michele Valori – commissioned by the IACP (Istituto Autonomo Case Popolari) to design a new residential complex approved under Piano di Zona no. 61/bis⁸, in the south-western periphery of Rome. The selected site lies between Via Portuense and Via della Casetta Mattei, on a hilly area equidistant from the historic center and the coast. An area of high morphological and environmental quality, still relatively untouched by building development. The plot covered 605,300 square meters and was intended to accommodate housing for the “general working population”, with a projected total of 8,512 residents, including 1,600 organized in cooperatives supported by the Gescal housing fund.

In 1970, when IACP selected the site, the area was almost entirely undeveloped, save for a few newly emerging residential pockets near Via della Casetta Mattei, just to the east of the site.

From the very first site visit, Fiorentino identified the preservation of the landscape as the primary objective of the intervention. This is clearly expressed in the project's technical report:

Given that the Corviale area marks a boundary between the city and a countryside still largely intact - and which the masterplan (PRG) intends to preserve through zoning constraints as agricultural land - we conducted in-depth morphological and typological research to ensure the development had a strong and defined identity. The entire western sector of the city has very particular physical characteristics: a sequence of hills punctuated by deep and articulated valleys, with built settlements mainly located on the higher ground, and two road systems: ridge roads and valley roads, the latter generally older, such as Via Portuense. The development area occupies one of these territorial emergences, and any scattered construction would have entirely compromised its current morphological appearance⁹.

During the first six months of 1972, the five teams worked together, comparing various settlement hypotheses. It was Fiorentino, appointed overall project coordinator, who proposed consolidating the entire building volume into a single linear structure positioned along the ridge. The aim was to create a unified work in which no single architect’s hand would be recognizable, and in which architecture, technology, and site management would coalesce into a cohesive and integrated plan.

As Giuseppe Cappelli later wrote:

[Corviale] was just a pie to be sliced up between many hands, and Fiorentino turned it into an architectural opportunity. He rejected the approved plan and, more importantly, refused to draw up another that would allow each architect to claim a section and carry out their personal ‘stylistic exercise’ in isolation. Fiorentino proposed a path that demanded real engagement from everyone, a difficult and risky path. He held no hierarchical role among the others, but having originated the idea, he naturally became general coordinator¹⁰.

The built project was the result of a long refinement process, evolving and simplifying from initial grid layouts to curved, and finally linear forms, over the course of two years of design work - until 11 June 1974, the date the final design was approved. Construction began on 12 May 1975 and was awarded to three building contractors: Manfredi S.p.A., Salice II, and Co.Ge.Co. Manfredi was assigned both the Corviale North and South segments - comprising the two major residential blocks. Drawing from his negative experience at San Basilio, Fiorentino strongly opposed awarding the construction of a single architectural unit to multiple firms. In a 1982 site visit with secondary school students, he reflected on the pros and cons of this choice:

Another undoubtedly experimental decision that proved misguided (but hindsight is always 20/20) was this: I believed the experiment should extend to the construction process. A linear structure like this was perfectly suited to being built on dual-track rails with cranes on either side, rising steadily like a long profile—250 metres at a time. That’s what we did: a single contractor. But then, industrial action erupted at the highest level in Italy, and that proved a major problem. […] Yet, in another sense, the decision was a success: it produced a high level of cohesion across the project. From the north to the south end, the building appears the product of a single technological and constructional hand—never mind the architect, who is always the last wheel on the cart¹¹.

The project area covered approximately 60.5 hectares, comprising residential buildings, service facilities, a system of pedestrian routes, roads and parking, and both private and public green spaces. The masterplan was structured around a single urban element: a one-kilometre-long residential block (Corpo I), located at the top of the hill, occupying a dominant position over the site and the surrounding rural landscape. Conceived as a strong horizontal marker in the relatively intact Roman countryside, the building follows a north-south axis, which defines the main organizational spine of the complex (fig. 5).

To the west lies a secondary residential slab (Corpo II), aligned parallel to the first, while to the east is the service complex known as Corviale Centro. Five transverse axes cut across the entire complex, with neighborhood services located at their intersections with the longitudinal axes. A third directional layer is added by a further linear building positioned at a 45-degree angle to Corpo I, symbolizing both practically and conceptually the umbilical link to the existing city. Designed with a mirrored cross-section, this building was to include three- to five-stories housing blocks depending on terrain elevation, with a covered ground-floor pedestrian arcade allocated to commercial units. This path was intended to connect with future service areas laid out in adjacent districts by the PRG, which - combined with those provided within Corviale - would have significantly reinforced the urban fabric.

The neighborhood is served by a one-way ring road, connected to Via Portuense and Via della Casetta Mattei, which encircles the area of Corviale Centro and defines a 50,000-square-meter zone reserved for primary urban-level services: the district headquarters, several facilities for commercial activities including the local market, the church, the public park, the theatre, the library, and a sports club. Beyond the ring, towards the city, a school complex was planned, comprising two primary schools and one lower secondary school, as well as an additional zone designated for sporting activities. Further east, at the edge of the site, stand six-stories residential blocks intended for the families of cooperative workers financed by the Gescal fund.

The decision to abandon the idea of a traditional neighborhood, as stated in the Report annexed to the Zoning Plan,

was part of the search for a new dimension of the habitat, conceived as a radical alternative to the sprawl of the current periphery, to the subordinate role it plays in terms of function and image with respect to the urban core, to the separation of residential areas from services and to the social downgrading that characterises it. The new Corviale is a large 'residential unit', a single housing complex that stretches continuously for about one kilometre and which, although it can be physically considered a single gigantic building, in fact contains and expresses through its architecture the complexity and richness of relationships proper to the city¹².

From an architectural perspective, Corpo I comprises eleven stories: eight residential floors, a service floor, the ground floor dedicated to distribution and cellars, and a garage level, reaching a total height of approximately 37 meters and a depth of 23 meters (fig. 6). The building’s full kilometer length is the result of the extrusion of a section composed of two mirrored volumes, separated by a four and a half-meter-wide slit that cuts through the building from ground to roof. The base of the building consists of a sloped plinth extending outward for about 36 meters, containing the garage and the ground floor used for circulation and storage (fig. 7). Vertically, Corpo I results from the stacking of two distinct building types: the first four stories are organized into flats of various sizes – 4, 5, 6, and 7 rooms – arranged in groups of four around a stairwell (fig. 8). Above this lies the entirely open “fourth floor”, originally intended partly for professional activities and retail, and partly for community use - the cantilevered volumes of the shared halls are located here. The top four floors return to a residential use, with flats accessed via internal galleries overlooking the central light well, which were also conceived as semi-public spaces for social interaction.

Five monumental stair towers, aligned with the transverse axes and designed as gateways to the entire complex, punctuate the rhythm of the building (fig. 9). These also define the subdivision of the building into five administrative units and provide vertical access to the gallery levels. In addition, twenty-six secondary stairwells reach all floors of the building. Given the exceptional nature of the complex, Fiorentino intended the main entrances to function as key urban episodes – actual squares in this linear city – lit day and night along with the stairwells and shared halls, each designed with a unique layout.

The main facade, facing east, extends almost uninterrupted for the entire kilometer of the building’s length. Only a few carefully positioned architectural elements break this continuity and enrich the overall design: the convex stair towers, the projecting glass-block volumes of the communal halls, the overhang of the gallery levels, and the deep shadow cast by the open fourth floor all contribute to a unified facade composition. The alternation between individual episodes and serial elements allows for multiple levels of interpretation and engagement, both at the scale of architectural detail and urban design. Special attention to the facade is also evident in the decorative panels of prefabricated concrete infill walls, designed by sculptor Nicola Carrino, whose aim was “to deny its own technological nature by recovering chiaroscuro effects, emphasized through the use of diagonal signs that change with the light” – an approach that introduced “variety within unity and austerity in this large residential building”¹³.

Corpo II, known among residents as the “Little Corviale” (Corvialino), is situated downhill and parallel to Corpo I. It consists of six two- and three-stories blocks, following the site’s topography, and accommodates flats accessed via open-air galleries and external staircases. These six volumes, each approximately 11 meters in height, are interspersed with service buildings and small shops located opposite the entrances to Corpo I, along the five transverse axes that structure the complex. Three of the service nodes house a nursery and a kindergarten (fig. 10), another features an open-air theatre and a restaurant, while the southernmost axis terminates in a panoramic belvedere overlooking the Tiber Valley.

Between the two residential blocks runs a broad tree-lined avenue planted with rows of linden and pine trees, designed primarily for pedestrian circulation and only occasionally for vehicles. At the intersection with the transverse axes, the buildings are connected by elevated pedestrian walkways, designed by Fiorentino and Cappelli, which provide direct access to the nurseries and kindergartens and also host a number of small essential-goods shops.

Interestingly, Corviale - regarded by some as Fiorentino’s architectural testament¹⁴ – encapsulates all the key themes that characterized his work: the opposition to low-quality, high-density speculative housing on the city’s periphery, lacking proper planning; the meticulous attention paid to housing quality and domestic space, with bright, spacious homes and panoramic views; and finally, the drive toward technological rationalization and optimization.

The two experiences described above - despite their markedly different formal and design approaches - ultimately shared a similar fate: one marked by urban decay, social marginalization, and a failure to integrate with the surrounding urban fabric. While San Basilio is often cited in the media as one of the capital’s key drug trafficking hotspots, Corviale has become a symbol of the ghettoization and marginalization of post-war social housing, and is frequently invoked as a paradigmatic example of so-called “bad architecture”.

Yet, from both theoretical and formal perspectives, the two neighborhoods are fundamentally different - starting with their geographical positioning, which is diametrically opposed: both are situated just within the boundaries of Rome’s Grande Raccordo Anulare, but while San Basilio lies in the city’s north-eastern periphery, Corviale occupies the south-western quadrant.

Their site plans, architectural language, land area, and overall urban scale all reveal radically different design strategies. These distinctions, however, do not detract from the shared ambition of counteracting the mechanisms of urban isolation and social hardship through architectural means.

In the 1950s, the proposed solution to such problems seemed to lie in the concepts of the “neighborhood unit” and the “quartiere” as foundations for community life-ideas aligned with Scandinavian models and the garden city movement, also theorised by Lewis Mumford in his 1954 essay The Neighbourhood and the Neighbourhood Unit. At San Basilio, the notion of introversion – within a neighborhood whose scale and formal qualities drew on a traditional and vernacular architectural language – was expressed not only through the morphology of the inner courtyards formed by the residential volumes, but also through the overall urban layout, which revolved around a central core designated for shared public services. The relationship with the wider urban context was mediated exclusively by the main road axes, which served as the only points of connection to the outside world.

Conversely, in the case of Corviale, public services were intended to act as a hinge between the new development and the existing city, with the aim of fostering a cohesive urban reality. The housing blocks, in turn, were designed towards the surrounding landscape, privileging openness rather than enclosure. Unsurprisingly, the issue of “large scale” – which had become central to architectural discourse from the 1960s onwards – progressively led to a broadening of the design scale, ultimately encompassing substantial portions of the territory within the urban project.

The social failure of these neighborhoods should thus be analyzed not solely, or even primarily, through the lens of their formal and compositional choices, but rather in relation to public policy and urban planning – or more specifically, the absence of a comprehensive social agenda integrated with the architectural one. Formal experimentation, even when authored by renowned designers and of clear architectural value, risks producing unlivable environments if not supported by a genuine economic and social diversity among residents, and by a long-term strategic vision capable of guiding the future of the city and its communities.

In Rome, as in many other Italian cities, what was lacking – despite the efforts of numerous architects and intellectuals of the time, including Fiorentino himself¹⁵ – was a coherent strategy to shape a unified vision of the new metropolitan city. An urban plan, for example, is capable of mitigating the risks associated with peripheral location, such as distance from the city center and infrastructural isolation.

In Corviale’s specific case, only a small fraction of the services envisaged in the original project were ever realized. Construction efforts focused almost exclusively on the residential units of Corpo I, while the other elements of the scheme were gradually and significantly scaled back. Following the bankruptcy in 1982 of Salice II – the contractor responsible for building Corviale Centro – the construction site came to an abrupt halt, ushering in a long period of stasis, functional transformations, and abandonment. In particular, the “fourth floor” of Corpo I, originally intended to accommodate commercial activities and communal spaces, was never completed.

Already by 1983, with the first housing units allocated, the first illegal occupations of vacant flats had begun. Then, from 1989 onwards, the entire open floor was gradually occupied, giving rise to numerous irregular residential units, which are today the focus of a regeneration project led by architect Guendalina Salimei.

Both San Basilio and Corviale are currently the subject of regeneration initiatives financed through Italy’s National Recovery and Resilience Plan (PNRR). However, the term “regeneration” risks becoming a hollow formula if not accompanied by a structured set of long-term and participatory actions. In some cases, it may even result in counterproductive outcomes, as exemplified by the so-called “Caivano model”¹⁶.

Any urban and social redevelopment project targeting these areas must necessarily combine physical investments – aimed at improving or even establishing essential services – with truly effective policies for social inclusion and a direct, active involvement of the residents. No real transformation can occur without recognizing local communities as protagonists in the process. After all,

architecture, which remains a superstructure, and the beauty it can undoubtedly generate, is not in itself sufficient to bring happiness, though it can certainly help create the conditions for it¹⁷.