In 1971, during Chile’s Popular Unity government, the Urban Improvement Corporation (CORMU) distributed a fold-out poster titled with the slogan ‘Now we go upward’ (Figure 1). Printed in blue and red on a white background, the poster is a montage of drawings, diagrams, and photographic cut-outs, interspersed with lines of text, each reading like a slogan:

The manifesto-like tone reveals a pedagogical and propagandist goal: to ‘go upward’ meant that, with the Popular Unity government, people were participating in a material progress manifested by high-rise housing projects. In them, the ‘urban man’ and the ‘new community’ could enjoy the light, views, and ventilation lacking in the one-story houses that crowded the city and contributed to its sprawl. At the same time, the construction of residential towers was intended to demonstrate the modern city envisioned by the State: vertical growth and better locations, liberating the ground for public use, with green spaces and public facilities.

However, the use of the word ‘now,’ suggesting a novel approach, was perhaps not strictly appropriate. In fact, many of the ideas the poster expresses had already been part of a project developed by CORMU that, at the time, was in its first stage of completion: the San Borja Remodelling (SBR). As an example of the corporation’s design and management abilities, the plan to build 28 residential towers of 22 stories each, standing like ‘a group of people who observe a street spectacle’ (Pérez de Arce 2016: 59) around a large park in the very heart of the city, was the testing ground for a new type of high-rise city (Figure 2). Although the vertical growth of housing in Chile dates to the 1940s with the four-story construction of the Huemul II and III developments (1943), new technologies, such as the elevator and the crane, allowed housing to grow vertically. In this process, the 12 residential towers built in the first stage of San Borja represent the most important and complex materialization of the new city’s movement ‘upward’.

Conceived and built during one of the most polarized moments of Chilean history — when political power passed from a center-leaning Christian Democrat administration (1964–70) to a left-wing Socialist government (1970–73) to a right-wing dictatorship (1973–90) — the SBR is the perhaps the most complex urban endeavor the State undertook in those years. Even though it has been mentioned in several studies about CORMU (Raposo and Valencia 2004; Raposo and Valencia 2005; Gámez 2006; Raposo, Valencia, and Raposo 2010; Aguirre, Cañas, and Vergara 2014), as well as in other publications (Labbé et al. 1969; Pérez de Arce 2016; Arze-Arce and Román-Crisóstomo 2018; Broquedis 2018), previous research has not fully addressed the richness and diversity of aspects that were brought together to materialize such a complex case. For some, ‘the San Borja project would confirm the unitary and totalizing formal will of the first, heroic period of modern urban planning’ (Pérez de Arce 2016: 61). For others, it was merely an example of ‘centralized urban policies and inward growth’ (IGM 1983: 206). It has even been portrayed as the result of a model of urban planning that was ‘technically, politically, socially and territorially centralized,’ with ‘marked degrees of utopianism,’ and an anti-urban, garden city bias (Sabatini and Soler 1995: 68–69). These assessments present the SBR as the stereotype of more general tendencies and attitudes attributed to late modern buildings, but they ignore and downplay the specific conditions that made it a case worthy of deeper attention.

In this text, we argue that instead of a preconceived, totalizing design imposed on the city, CORMU proposed a strategy to achieve urban renewal as a case by case process. Since the corporation had to undertake urban improvement — that is, operate on consolidated areas instead of expanding the city outwards — its proposals depended on knowing key factors of the context, such as the availability of urban land, but also on being adaptable to changing conditions. Furthermore, since CORMU was formed by architects with no previous bureaucratic experience, they tended to devise specific arrangements to achieve a goal so ambitious that it pushed the limits of the State apparatus and the country’s building industry. Rather than resorting to preconceived planning recipes and solutions, the creators behind the San Borja project employed ad hoc, pragmatic approaches contingent on the specific situation and circumstances of a particular case. Here, we use the original Latin definition of ‘ad hoc’, which means ‘to this end,’ moving away from the so-called adhocism concept coined by Charles Jencks and Nathan Silver (2013). Our purpose is to highlight what we believe encompasses both the tools and the spirit that drove the case to its concretion: the mobilization of the industry’s capacities and the State’s instruments to materialize a design that was beyond their capacities. This ad hoc approach is confirmed by the unusual materialization of a large-scale urban project funded through atomized, individual real estate mortgages. In so doing, the present text sheds light on an urban design history of State-led intervention in Santiago that is distinct from the generic forms of centralized planning but also from the laissez-faire of neoliberal urbanism.

The article unfolds its arguments along a path that winds through the history of the San Borja project. Drawing on the existing literature, as well as interviews with the project’s architects and the scarce archives available on CORMU, this article investigates the project from four distinct perspectives. First, we analyze how the Chilean State armed itself with the necessary tools to carry out a project like this, studying CORMU’s origins and its organizational structure. Then we focus on the financing scheme, a strategy that turned existing market instruments into an opportunity for public intervention. We then investigate the ways in which this project tried to build a new community. Finally, we explore the tender mechanism used in the realization of the SBR that led to the customization of the generic tower and achieved a fruitful connection between the State and the private sector. By revisiting and accounting for the complex conditions that made this project possible, this paper also shows how those conditions were again transformed after CORMU was dismantled during the brutal Chilean dictatorship.

The right-wing Chilean president Jorge Alessandri (1958–1964) stubbornly dismissed the chance to create an entity to unify the various State departments dealing with housing, although he had known of the idea before taking office. When he was president-elect, he had discarded the suggestion of creating a housing agency within the Ministry of the Treasury modeled on the US Housing Agency, a recommendation made by a US mission on September 22, 1958 (Robinson 1959: 243 and annex 30). Shortly after, in 1959, he ignored Senator Eduardo Frei Montalva’s proposal for a ministry of housing in charge of absorbing the different funds and merging them with the tasks of the active Housing Corporation (CORVI), in operation since 1953 (Robinson 1959: 243 and annex 8). Not even the major earthquake in Valdivia in May 1960 — at 9.5 on the Richter scale, it left about 300,000 people homeless (Gil and Atria 2021: 19) — made him change his mind.

At this time, the United States had a strong presence in Chile: the Klein-Saks mission of 1955;2 experts sent by the Ford Foundation (Gorelik 2023); the awarding of Fulbright scholarships to study in the US; consultancies to the Chilean government from the US administration; and the Alliance for Progress loans for reconstruction after the Valdivia earthquake. Beyond the evident influence the US sought to have in Chile during the Cold War, and under the all-encompassing discourse of development (Escobar 1995), US missions abroad had the goal of rationalizing production and reducing debt and inflation in countries of geopolitical and economic interest; these conditions were essential for making the economy work and, with it, scaring away the ghost of communism. To this end, production and territory had to be subordinated to planning, a new technique promoted in Chile by John Friedmann, a consultant sent by the Ford Foundation in 1965 (Monti 2020).3

When the Christian Democrat leader Frei-Montalva became president in 1964, it was no surprise that he proposed two new State entities: the Planning Office (Oficina de Planificación, ODEPLAN) and the Ministry of Housing and Urbanism (Ministerio de Vivienda y Urbanismo, MINVU). The latter would be in charge of four corporations that would coordinate to carry out different aspects needed for housing construction. These were the existing Housing Corporation (Corporación de Vivienda, CORVI), responsible for building units; the Dwelling Corporation (Corporación Habitacional, CORHABIT), dealing with financing and allocation; the Urban Works Corporation (Corporación de Obras Urbanas, COU), developing urbanization projects, networks and infrastructure; and the Urban Improvement Corporation (CORMU), responsible for purchasing land and defining sites for new housing projects. Disregarding Friedmann’s recommendation for a planning model that would focus on community empowerment, the government established an institutional framework of centralized planning that instead empowered the State (Raposo and Valencia 2004: 119).

Following the promulgation of Law 16,391 establishing MINVU and the start of its operations on December 16, 1965, the task was to set up the new corporations that would complement the Housing Corporation. Although the Urban Improvement Corporation was instituted via Decree 483 on August 25, 1966, the climate of ideas that gave rise to this type of corporation had been in the air for more than a decade. In the United States, in 1954, the government had enacted its second Housing Act, amending some omissions from the 1949 Act.4 One of the modifications was the inclusion of the concept of ‘urban renewal’, which prompted the renovation of deteriorated urban areas and the eradication of slums, both to maintain a ‘decent’ urban image and to boost the economy through construction. The aim was to mobilize the power of the State to clear the ground for private investment in city centers. These USA-born strategies were quickly implemented in post-World War II Europe, where many urban centers were to be reconstructed. And they also touched ground in Chile.

On December 3, 1958, Ralph Taylor, director of the Urban Renewal Agency of New Haven, Connecticut, landed at the Cerrillos airport in Santiago. He had come at the request of the local Ministry of Public Works to provide technical assistance in the upgrade of Chilean cities. Among his recommendations, which sought to promote urban renewal at no cost to the State, the first was ‘to create the Urban Reform Corporation (CORE), to stimulate interest and empower the implementation of urban renewal projects’ (Robinson 1959: 72 and annex 52). This recommendation probably influenced the proposal made in 1964 by the Chilean Chamber of Construction to create an ‘Urban Improvement Corporation’, defined as ‘an entity to facilitate the reconstruction of the old areas in the main cities’ (Raposo and Valencia 2004: 116). After taking office as the first Minister of Housing and Urbanism, Modesto Collados did not consider any of these legacies. However, he did indicate that institutions like the soon-to-be-created CORMU already existed in other countries, observing that ‘in Spain, for example, it is called the Urbanization Management Office and has had considerable influence in the progress Spain made in terms of housing’ (cited in Raposo and Valencia 2004: 116). With this statement, Collados not only ignored the political context in which such an institution was formed; he also failed to acknowledge that CORMU’s organizational structure was curiously similar to the one created in 1959 by Franco’s dictatorship.5 All these legacies shared the principle that this corporation had to be the State’s arm in the land market, and it should work hand in hand with the private sector. However, none of them could have anticipated that, with unexpected political support, the Chilean version would break from these precedents.

Perhaps due to his experience as Minister of Public Works during the presidency of Juan Antonio Ríos (1942–1946), President Eduardo Frei-Montalva (1964–1970) was interested in the type of projects carried out by the newly established corporation. In a recent interview, Patricio Gross, the former head of CORMU’s Urban Development Sub-Department, commented that Frei-Montalva ‘was fully convinced, brutally convinced’, to the point that ‘he would appear at our offices every so often to see how the project was going, and even suggested ideas’ (Gross 2021a). Under the slogan ‘Revolution in Freedom’ — that is, a revolution without class struggle — Frei-Montalva’s government intended to be transformative with a technocratic bias, placing trust in planning and technical teams rather than community participation (Cáceres-Quiero 2017). Therefore, beyond the principles associated with its establishment, CORMU was in fact a design department for a government that wanted to implement concrete and quick urban transformations.

In line with ideas of urban renewal, the CORMU was to ‘recover consolidated areas in a state of deterioration’ and ‘reduce the tendency to live in the periphery’ (Jara 2019: 138). This meant intervening in city centers through new urban models that could ‘change the existing image of downtown areas — … with narrow streets … generating a feeling of confinement and suffocation — for one that would open the city’ (Jara 2019: 138). To make better use of the available urban infrastructure and limit the city’s expansion towards the periphery, the challenge was to densify without overcrowding. To achieve this, the decree that created CORMU listed 16 functions; among them, the following are of particular interest:

These legal capacities — which in fact mandated CORMU to renew instead of preserve the city — largely explain the type of projects this institution carried out, as well as the scope and radicality of some of them. With regards to CORMU’s competencies, it is worth highlighting two crucial aspects. First, the enactment of Law 16,615 issued on January 20, 1967, an institutional reform that eased the State’s capacity to expropriate land. This law amended the Political Constitution of Chile to simplify expropriations under the principles of ‘the public interest’ and ‘the social function of property’. The latter included ‘whatever is required by the general interests of the State, public utility and health, the best use of productive sources and energies in the service of the community, and the improvement of the living conditions of the common people’.7 This reform was crucial, as it allowed the Chilean government to ‘carry out the Agricultural Land Reform, its housing plan and urban remodeling’ (Un Programa y un Gobierno 1967: 116–117),8 and facilitated these processes by deferring payment for the expropriated property for up to five years. In simple terms, the State did not need to have the money in advance to seize the land: it could take it, develop it, and then use the revenues of such development to pay back the original owner. The second crucial point was that the corporation was allowed not only to acquire land but also to design and remodel. But what seemed to be a way of hiding its underlying purpose — a State intervention in the land market to encourage private investment and building industry — became, in fact, CORMU’s primary function. The mandate of designing and remodeling entailed the unique opportunity to rethink and redesign entire parts of the city, and CORMU’s cadres would not take this lightly. Taking advantage of the double capacity to acquire land and to design, they focused on reimagining cities through concrete projects, instead of long-term master plans or planning instruments. Urban design exceeded the mere support to private investment, to the point that the corporation’s architects went beyond their duties (Raposo and Valencia 2004: 133). This fact also established a primacy of design over planning — an approach strongly criticized by urban planners, as is discussed later.

Prior to dealing with these critiques, let’s return to San Borja. Before renewing 18 hectares in the middle of the city could even be considered, the primary condition was to own the land. The Health Service’s decision to move the San Borja Hospital freed up a large plot of State land in front of the Alameda (Santiago’s main east–west axis) and steps away from Vicuña Mackenna (one of the main north–south avenues). Since this location was ideal for testing the corporation’s abilities, the process began, in April 1967, with the acquisition of these plots, prompting the beginning of the project and giving it its name.9 The previous demolition of the nearby Hospice of Santiago, to open Diagonal Paraguay and Curicó streets and build the Emergency Hospital (1967), added another large plot between Marcoleta, Portugal, and Diagonal Paraguay streets (Arze–Arce and Román–Crisóstomo 2018). In this scenario, the opportunity to demolish the Juan Antonio Ríos Market (currently housing the Faculty of Architecture and Urbanism of the University of Chile), along with the clearance of some private properties on the Alameda and Portugal Street (Labbé 2021a), would allow for the consolidation of a plot large enough to demonstrate CORMU’s version of urban renewal. (Figures 3, 4)

Due to delays from the Health Service, however, the old hospital was not demolished until 1976, when the first twelve towers of the SBR were already completed (Figure 5). Since the plot of the former Hospice of Santiago received towers 7, 8, 9, 10, and 11, the land for towers 1, 2, 3, 4, 5 and 6 had to become available in a fast-track way: around 300 plots were expropriated and its constructions demolished in less than a year (CIDU-PLANDES 1970: 77). For Ernesto Labbé, a CORMU architect and the SBR project coordinator, clearing these edge plots was necessary ‘because it couldn’t be a landlocked intervention; it made no sense if it was not open to the city’, even though this process was ‘very painful because people didn’t want [to leave]’ (Labbé 2021a), and it wasn’t easy, ‘because they didn’t want to receive what we paid them’ (Labbé 2020). Therefore, without the constitutional amendment that allowed expropriations on the grounds of the social function of property, this project would have never been possible (Gross 2021a; Labbé 2021b; Lawner 2021b). The fact that the State could defer the payment of such well-located land may have also helped (Gross 2021b; Lawner 2021a).

The SBR took full advantage of this unprecedented legal scenario. But it did so by exploiting the full capacities of the State, which had not only the power to enforce the law but also the ability to justify its actions. In a democratic constitution, as the Chilean one was at the time, the State could not simply pass over property rights. Since expropriations had to be grounded on social reasons, the action of the State had to rely on an argument that justified the social need for the claimed land.10 In the case of the SBR, the argument was densification: the potential for many people to benefit from urban infrastructure and good location. The tool to present this argument was a design that, using isolated towers surrounding a park, could make land use more efficient, offering sunlight, views, ventilation, and green areas to a population that, until then, had lived in a low-rise city. These were the features highlighted through the alluring images of promotional brochures (Figure 6). In other words, to claim the social function of property, the State needed an architectural design.

In Chile, State-led housing projects are meant to be allocated to its users rather than sold on the market. However, the SBR was not just any project. As a market tool to attract buyers, advertising should not be required by a State that provides housing to those who cannot afford it. But the fact that the SBR had an advertising campaign reveals its distinctive character. While most State projects sought to reduce a housing deficit and had a ‘captive’ clientele, San Borja was conceived with another goal: to renovate a deteriorated area and show a new way of designing the city. Because of this, it could not count on the centralized funding the State gave to social housing. Thus, although CORMU had already seized the land, it was missing the funds necessary to erect the buildings.

To build this complex, therefore, CORMU devised an original strategy to finance the construction: use the individual mortgage credits from existing savings funds, which were backed by the State. Until then, the backing for middle-class housing came from the pension savings banks, and only in some cases did the State contribute part of the funding. However, the creation in 1960 of the Central Savings and Loans Fund through Decree DFL205, which also governed the creation of the Savings and Loan Associations (Asociaciones de Ahorro Previsional, AAP), allowed the State to control the proliferation of savings banks and to back up the money they administered.11 In fact, when the State started to back up the AAPs, their ability to raise capital from savers increased (Ruiz-Tagle 1975: 354). In this way, the DFL205 established a mechanism for savings, guarantees, and loans to promote ‘savings and the acquisition and construction of housing’.12 This mechanism, in which the State ensured the protection and proper management of the savings, was known as the National Savings and Loans System (Sistema Nacional de Ahorro Previsional, SINAP), and it was focused on middle-class housing.

The SBR units were not to be acquired through State financing managed by CORHABIT, which covered the low-income range (Arellano 1977: 62). Instead, they were conceived under the umbrella of middle-class-oriented SINAP loans. Yet, when the project was under construction, CORMU established its own sales office (Valenzuela 2021; Lawner 2021b). Located in Alameda 258, in one of the few buildings not demolished to build the SBR, this office oversaw sales and collection, and, in most cases, it also absorbed previous sales made through SINAP.13 In advertising posters, for example, they offered ‘extraordinary credit aid and also financing through Savings and Loan Associations’ (Figure 7). This financing framework shows that the project’s scope led CORMU beyond its capacities: despite being a State agency, the corporation performed retail real estate sales. In so doing, an agency like CORMU, which operated under the Ministry of Housing and Urbanism, was allowed to absorb some operations of SINAP, an agency under the Ministry of Finance.

State-backed SINAP loans were also crucial for the SBR project brief. As some of its authors have indicated, the reference for the San Borja towers was the Baquedano building, inaugurated in 1966 (Labbé 2021a). Located a few steps away from the SBR, on the corner between Alameda and Vicuña Mackenna avenues, this 20-story tower with an almost square floor plan, and with six apartments per floor of around 70 square meters each, was built by DESCO and designed by Sergio Larraín García-Moreno, Ignacio Covarrubias, Jorge Swinburn, Carlos Bolton, Luis Prieto, and Armando Lorca (‘Edificio Baquedano’ 1969). This case demonstrated the technical feasibility of building a residential tower in Santiago and the possibility of selling it in that area of the city. Since that real estate endeavor relied on SINAP mechanisms, CORMU took it as both a formal and a financial example. In fact, the SBR would repeat 28 times the formal and financial logic of the Baquedano building. The tower with square floor plan of 20 to 22 stories became the base module that began to be distributed over the acquired land and those yet to be expropriated, with the towers moving like chess pieces on an abstract, orthogonal board (Miranda 2021). The tower, in this way, became the tool for conquering a piece of urban land.14

The previous decision had several implications. On the one hand, without market research or the State funding that social housing guarantees, CORMU defined a base unit according to ‘a practical examination of the market’ — that is, imitating another building that worked well — ‘since a detailed market research [was] practically impossible’ (CIDU-PLANDES 1970: 79). On the other hand, it meant that the simultaneous construction of the first 12 residential towers relied on the condition that middle-class buyers could obtain a particular kind of mortgage credit. In other words, the entire operation relied on an atomized financing model for which urban renewal was to be paid for by San Borja’s new tenants, as pointed out by Jaime Bellalta, the head of CORMU’s technical department (CIDU-PLANDES 1970: 116). This exceptional strategy — a sort of urban-scale crowdfunding — took existing market instruments as the basis for a public intervention that, due to its scale, sought to transform the same market: through an oversupply of units, the aim was to contain the rise in housing prices, just as central banks take measures to contain inflation (CIDU-PLANDES 1970: 119).

But not only that. Since the financing system assumed a standard credit model, a certain socioeconomic homogeneity was inserted into an area in a short time. If each of the twelve towers built in the first stage had about 120 apartments of 70 square meters each, 1,400 new apartments of the same size were created in less than five years, which could have housed approximately 5,000 people. It is also worth noting that the assumption underlying an urban transformation of this magnitude — the traditional nuclear family as the base unit — allowed for the activation of the whole system of middle-class mortgages. The apartment size was crucial for including three bedrooms, a bathroom, a living-dining room, and a kitchen, in what seemed the appropriate spaces for a middle-class family: a heterosexual couple with two children (Figure 8). It is therefore no surprise that the Popular Unity government criticized this project, considering it ‘too bourgeois’ (Raposo and Valencia 2004). Nor is it a surprise that the SBR real estate ads targeted young couples, inviting them to build their lives in this complex (Figure 9). The family unit of two parents with two children was thus the tool for introducing a new form of urban domesticity and downtown renewal. Consciously or not, the SBR turned the middle-class family into not only the method by which to finance urban renewal but also the argument for its justification.

However, for these middle-class families to live their entire lives in San Borja — as is proposed in one of the ads — more than 70 square meters per family was needed. The shared park and the open spaces were intended to play a role in extending living space; according to the creators, such spaces would be ‘like bringing to the city center the best of the countryside’.15 Although it is tempting to read this phrase as a new urban development trying to mimic the suburbs (Stevens 2016), this was not actually the case. In Chile, there was still no suburban expansion to imitate. The model was literally the countryside. The proposal of a group of towers within an urban park was radically unprecedented. And it posed a huge challenge.

The main challenge was the quality of the shared green spaces — a problem that had been the Achilles’ heel of many modern projects worldwide (Figure 10). In a decision that shows how far CORMU’s architects would go to ensure the SBR’s success, the corporation itself committed to the maintenance of these spaces over time (Labbé 2020, 2021a; Lawner 2021a, 2021b). Yet, since the State could not spend its budget on private properties, the way to fix the problem was even more radical: common spaces would be owned by the CORMU, leaving as private property only the base of the towers — the 22 x 22 meter footprint. This means that each tower had 100 percent land occupation and a floor area ratio of 22, and since the four facades were also party walls, all the windows were illegal (Labbé 2021a).16 To overcome this normative impasse, the architects argued that since CORMU was part of the State, its properties could be considered public space, like a street, and urban regulations allowed windows on facades facing public spaces (Labbé 2021a). The power of such a symbolic project for the Frei-Montalva administration must have facilitated the approval of these arguments by the Municipality of Santiago, which at the time was in the hands of a Christian Democrat mayor appointed by the president.17

By making the land open and available for the community and the city, the State turned it into a public good. Going far beyond its established functions while taking its capacities to the maximum, CORMU demonstrated a genuine concern for the fate of its project. Such commitment continued after 1970 when the Popular Unity government came to power, highlighting the importance of continuing to ensure these spaces remained open to the public and in good condition. Miguel Lawner, CORMU’s head during Allende’s government, said in an interview that when the apartments of the first phase were handed over to their new owners (circa 1972), they immediately established a community organization between the towers, which published a magazine and organized Christmas celebrations among other events; ‘the sense of participation was admirable’ Lawner recalled (2021a). The same community organization also owned the thermal power plant built between 1970 and 1972. To administer it, the CORMU’s director, Nicolás García, envisioned some form of ‘administration in the project, not as a cooperative but rather in a quite capitalist way’ (CIDU-PLANDES 1970: 82). The idea was to create a sort of LLC in which homeowners would be shareholders so that they could manage and profit from the rent of heating, water, sports facilities, parking lots, and commercial spaces. Although this LLC still exists under the name of COSSBO (Community of Services of San Borja), it currently manages only the heating and water services for the SBR, the only things the towers still share.

The original community facilities continued to operate until the dictatorship dismantled CORMU in 1976, transferring its properties and functions to the new Housing and Urban Development Service (SERVIU). One year earlier, on April 12, 1975, the regime had issued Law 966 to change the economic structure of the country through its Program of Economic Recovery, ‘to accentuate the policy of reducing the size of the public sector and its current expenses’.18 Commonly known as ‘The Shock Therapy,’ this program was the first step in Chile to shrink the State and shift economic policies towards neoliberalism (Délano & Traslaviña 1989). It was then that the fragmentation, alienation, and privatization of the SBR’s common spaces began. The project was never completed, and some of these shared spaces were sold to third parties. Others were fenced by the towers’ inhabitants. This is why today the area is a bleak urban landscape of fences and subdivisions (O’Ryan 2021) (Figure 11).

However, a study conducted in 1989 showed high levels of satisfaction among the SBR inhabitants; the only complaint was that the project had not been completed. The results of this study counter the idea that ‘urban renewal strategies linked to high-rise projects are not viable because people don’t want to live in towers’ (Figueroa and Larraín 1989: 85). The study’s conclusions are impressive, considering that, during the Chilean dictatorship (1973–1990), the SBR was not only criticized by neoliberal urbanists as a symbol of the centralized planning of an allegedly inefficient State, but it was also heavily raided in the search for left-wing activists who opposed the regime (Bastías 2021).

The fragmentation of common spaces after the dictatorship was only possible because of one of the main features of the project: for the SBR, the existing urban fabric was not the organizing principle. Instead, the articulation between towers, parks, and common spaces was conceived to replace the existing urban structure with a model capable of extending in different directions. Gross said that ‘the original project was to reach Forestal Park to the north and extend to the south through Portugal Avenue’ (2021a). The expansive condition of the project was demonstrated by towers 23 and 24, which were part of the second stage of implementation, located almost 500 m away from the rest of the complex, as well as in the Diez de Julio Sectional Plan, an unrealized proposal to extend the SBR nearly 2 km south of the Alameda.19

The other expansion sought was related to the construction industry itself. At a moment in which Santiago had no more than ten residential towers — the tallest being 27 stories20 — the proposal to simultaneously build 28 buildings, 20 to 22 stories high, was an unprecedented challenge for the construction industry. This was among the project’s goals: the State had not only to design urban renewal but also to help develop the capacities to carry it out (Gross 2020).

With the 22-story square-plan tower as the base module of the densification model (Raposo and Valencia 2004: 135), and an urban design that considered every tower as an isolated unit, the buildings could be built in parallel by different teams. The CORMU therefore opened the SBR to a tender model in which teams of construction companies and architects could participate by offering to design and build one or more buildings. Although there were some elements of the original SBR design for which no proposals were received, such as low-rise 4- and 12-story buildings, the towers were very attractive to builders and architects, and the 12 towers of the first stage were awarded to six different teams.21 This strategy had several implications. While all the towers have the same form and volume, their designs were different, favoring creative interpretations of a generic model and thus providing aesthetic variability. The scheme also ensured the project’s viability by diversifying the agents in charge of building it: if a company failed to deliver on time or went bankrupt, others would manage to finish, generating competition between them regarding deadlines and construction methods. This condition, moreover, made it possible to explore alternative building systems, which, in turn, resulted in the generation of new capacities in the industry. For instance, if six companies competed to obtain elevators, cranes, windows, and other elements, the construction industry would be forced to grow and a virtuous circle would begin. The competition between different construction companies, each developing their own approach, transformed the SBR into a testing ground for the entire construction industry in Chile (Gross 2020, 2021a, 2021b; Labbé 2021a) (Figures 12, 13).22 However, pushing the building industry to develop the capacity to build towers also came with a downside: these companies would want to keep using that capacity in the future. Soon the question arose of what to do with the ‘pressures from these companies that will want to build only towers to amortize their large investments in crane equipment suitable only for high-rise buildings’ (CIDU-PLANDES 1970: 71). And it was not an ungrounded concern. In fact, when neoliberal policies undermined the role of the State, these building companies were free to look for sites where they could put their new capacities to work. Although it is beyond the reach of this article, a quick look at Santiago’s urban landscape today would easily show that such capacities have been widely used.

Since the SBR was the most significant urban intervention the Frei-Montalva government could show, the competition between the companies to finish first was fierce (Figure 14). But the rush to have new buildings visible to the city was, in many cases, at the expense of their use. As CORMU architect Sergio Miranda recalls, ‘[since] all the money was spent into what was visible […] the people said, ‘for God’s sake, this government invests really well’’ (2021). However, when the sale of the apartments began, the buildings looked finished but were not yet inhabitable, and the new owners had to wait for years to receive their flats (Valenzuela 2021). Miranda continues: ‘Luckily […] it didn’t turn into a big scandal, but the truth is that the deliveries were stopped for a long time’ (2021). This situation sparked controversies between the administrations of Allende and Frei, since the incoming government had to complete a project that was not in its plans and did not fit its political and ideological program (Raposo and Valencia 2004: 130). For the CORMU team during the project’s first stage, the possibility that another administration would complete the project was never considered.23 With Frei’s large flow of votes, ‘there was a belief that this government would last 30 years’ (Gross 2021a).

Some controversies also extended into debates about the city. In 1969, AUCA magazine organized a conversation between Ernesto Labbé and Fernando Castillo-Velasco. The latter, the architect of the Tajamar Towers (1967), argued that the tower was an ‘anti-citizen element’ that existed only to multiply the most expensive plots vertically but was a mistake in urban terms, because ‘it makes the life of man [sic] on the ground unbearable’. Thus, ‘towers should be located in the city center only as landmarks, but never to make it denser’. To conclude his point, he said that ‘cities should be concave, with low areas in the center at the scale of the pedestrian, and the high towers on the outside, widely distanced to enjoy nature’ (Castillo-Velasco and Labbé 1969: 63). For his part, Labbé, the SBR project coordinator, argued that towers responded more to a ‘different use of the emptied land than to the density concerning the land value’. He explained that due to its location, the SBR had a metropolitan character, and therefore a higher density was needed to justify the intervention. In this logic, ‘by concentrating housing in a perimetral ring, in contact with Santiago, with a minimum floor occupation (towers), the emptied area (70%) was destined for metropolitan facilities (parks, services, and commerce)’ (Castillo-Velasco and Labbé 1969: 61–62). Although both were against leaving the fate of cities to the real estate market, their visions were different. While Castillo-Velasco was probably thinking of compact, low-rise, continental European cities as a model and followed a more formalistic idea toward the urban question, Labbé and CORMU had a more pragmatic approach in which feasibility took precedence. Yet this ad hoc approach also sparked criticism from urban planners, mainly because despite of the lack of data — population, income, urban tendencies, etc. — CORMU still undertook the ‘settlement of a significant number of people with specific social conditions, which would have implications for the political and administrative organization’ (CIDU-PLANDES 1970: 92). Bringing these critiques to the forefront helps us realize how different the CORMU’s approach was from other paradigms: it was neither scientific planning nor formalist architecture. It was not socialist, but neither was it laissez-faire neoliberal urbanism. Perhaps due to this, the SBR received criticism from several directions, even before receiving its first inhabitants.

In less than six years, between 1967 and 1973, 19 of the projected 28 towers were completed. These towers would become one of the symbols of the complex political process that Chile was experiencing. For instance, by the start of 1973, the SBR was seen as the icon of Santiago’s modernization, as one of the covers of En Viaje magazine shows (Figure 15). A few months later, however, things would radically change.

On September 23, 1973, twelve days after the coup d’état, the San Borja Remodeling project was the site of military raids and even the public burning of books forbidden by the regime. The entire complex was raided, rather than any specific tower (Figure 16). With people denouncing their neighbors — as shown in the recordings of the raid24 — social bonds were quickly broken. The SBR was therefore besieged not only by some architects and planners but also by the military and, ultimately, by neoliberal ideas.

Although the SBR may have demonstrated the capacities of the State to build the city, one of its features could have paved the ground for a smooth landing of its opposite: the neoliberal city. Since its construction relied on competition between several building companies, the SBR became the testing ground for new techniques that helped level up the building industry in Chile. Just a few years later, however, in a neoliberalized urban land market with almost no State intervention, these capacities were widely mobilized throughout the city. In this way, real estate towers became the mushrooms that, even in small plots, grew over the ruins of the developmentalist State.

This collateral effect was hardly intentional. When the SBR was conceived, there was no way to foresee the brutal radicality of what would come later. Fortunately, buildings last long enough to allow us to look, through them, toward a moment in history when things were different — in this case, a moment when public agencies of a relatively poor country managed to lead a change of scale in the city. Looking at those instances matters now because, after CORMU was dismantled in 1976 due to the neoliberalization of the economy and its consolidation in the 1980 Constitution, another moment like that is hard to envision.25

However, if we were ‘to ask what the conditions of possibility of architectural projects were,’ as Levin (2015) suggests, we would realize that the SBR is not the mere result of the sum of conditions. Although it arose out of the sudden and unplanned availability of well-located urban land, the opportunity was squeezed to its maximum, to the point that it gave meaning to CORMU’s work by pushing it beyond its initial capacities. This was not the usual State housing complex that repeated a type to reduce costs and increase the available units. On the contrary, the SBR had a highly specific urban design, a base module adapted and customized during its execution, and its development required a series of ad hoc strategies and resolutions that were necessary to achieve a project that would seem impossible had it not been built.

In the end, the SBR is a complex and situated project that does not lend itself to being reduced to a single idea, trend, or intellectual trajectory. To avoid that trap of a simplifying narrative, we looked at it from various points of view, just as the first 12 towers surrounded the park while witnessing — like a group of people observing a street spectacle — a city growing upward while the State apparatus was torn down by a brutal dictatorship and its economic policies.