Iron architecture: the light and steam of industrial Catalonia

In the 19th century, the Industrial Revolution not only changed the way people worked and lived, but also profoundly transformed architecture. The arrival of new materials, such as cast iron, wrought iron, and glass, opened up possibilities that had previously seemed unthinkable: covering large spaces without the need for thick walls, building lighter structures, and harnessing natural light like never before.

In Catalonia, this new way of building grew at the same pace as industry and cities. Markets needed large spaces to accommodate an ever-increasing population, factories spread along rivers, and transport infrastructure became increasingly important. Iron became a symbol of this transformation: a material that represented modernity and that ended up leaving a very visible mark on Catalan architectural heritage.

An architecture born from industry

For centuries, stone, brick, and wood had been the primary building materials. But erecting large buildings with these resources required heavy structures and numerous support points. Iron changed that. Thanks to metal columns and large trusses, it became possible to cover vast areas, create more open interior spaces, and allow light to reach even the deepest corners.

This architecture is characterized by its exposed structures, lightweight roofs, skylights, and large interior spaces. Many of the metal components were manufactured in specialized workshops and then transported to the construction site for assembly. This system facilitated construction and directly linked architecture with advancements in the metalworking industry.

But iron architecture was not merely a matter of engineering. Columns, railings, and ornamental elements often incorporated elaborate forms, demonstrating that functionality could also be accompanied by beauty. In many buildings, the structure was not hidden behind the walls but became the dominant feature of the space.

The markets: large spaces for a growing city

One of the best examples for understanding the possibilities of iron is the covered markets. As Barcelona grew, facilities were needed that could accommodate numerous stalls, facilitate the movement of people and goods, and guarantee adequate ventilation and lighting. Large metal structures offered an ideal solution to these needs.

The Born Market, built in Barcelona during the 1870s, is one of the most representative examples of this architectural style in Catalonia. Designed by Josep Fontserè, with a metal structure by the engineer Josep Maria Cornet i Mas, the building is notable for its large halls, roofs, and cast-iron columns. The metal components were manufactured by La Maquinista Terrestre y Marítima, one of the most important industrial companies of the time.

The market functioned for decades as an essential facility for supplying the city, until the relocation of wholesale activity to Mercabarna changed its role. Its history took a new turn when archaeological excavations uncovered the remains of 18th-century Barcelona beneath the pavement. Today, the Born Centre for Culture and Memory allows visitors to explore this past within the same iron structure that was erected in the 19th century.

Another outstanding example is the Sant Antoni Market, inaugurated in 1882 and designed by Antoni Rovira i Trias. Its layout, organized around four large wings surrounding a central space, responded to the needs of a growing neighborhood. After extensive renovations, the market reopened in 2018, combining the preservation of its historic structure with new spaces and underground services. More than a century after its inauguration, it remains a vibrant facility that demonstrates how industrial heritage can be adapted to current needs.

Industrial colonies: factories that created towns

The industrial transformation was not limited to the large cities. Along the Catalan rivers, especially the Llobregat and the Ter, industrial colonies proliferated, complexes that brought together factories, housing, and services in a single space. Water provided the energy needed to power the textile machinery, while the proximity of the workers facilitated the operation of the companies.

A factory colony could include workers' housing, a church, a school, a store or company store, and the residence of the owning family. More than just factories, they were small population centers organized around industrial activity. Their architecture reflected this dual productive and residential function, with large factory buildings alongside buildings intended for daily life.

This model also had a social dimension that must be considered. Work, housing, and a large part of the services depended on the company itself, which profoundly shaped the lives of the workers and their families. Therefore, the industrial colonies are a heritage that allows us to understand both the technological advances of the time and the inequalities and forms of social organization that accompanied industrialization.

Among the best-known examples is the Sedó Colony in Esparreguera, which became one of the country's largest industrial complexes. Today, its heritage allows us to discover the scale of that activity and understand how a factory linked to hydroelectric power operated.

Also noteworthy is the Colonia Güell in Santa Coloma de Cervelló, developed by the businessman Eusebi Güell. The complex preserves industrial and residential buildings of great interest, but it is especially famous for its church, designed by Antoni Gaudí. The crypt, with its innovative forms, materials, and structural solutions, was a fundamental architectural laboratory for the architect's later work. It is a unique example of how the industrial world could also become a space for artistic experimentation.

From iron to modernism: a new way of building

Iron architecture paved the way for a new relationship between technique and aesthetics. What had initially been developed to solve practical needs ended up offering architects new expressive possibilities. Iron allowed them to draw curves, create slender structures, and work with decorative elements with a freedom that traditional materials did not always facilitate.

These possibilities continued into modernism, which incorporated wrought iron into balconies, railings, doors, and other ornamental elements. The material ceased to be exclusive to factories and markets, entering residential buildings as well, where it was combined with stone, ceramics, and glass. The boundary between architecture, craft, and industry became increasingly blurred.

Today, historic markets and former industrial colonies allow us to experience this transformation firsthand. Looking at the columns, trusses, and roofs is to discover an era when building meant experimenting with new techniques and imagining different cities. Iron architecture was not only the expression of an industrial Catalonia: it laid the foundations for a new way of understanding space, light, and the possibilities of modern architecture.