If we cast any eye over the roll-call of metallurgical companies in Gipuzkoa, we soon see realise that the most potent image of the industry is one of rows of industrial bays. The bay, a rectangular space with its twin-sloped roof, was one of the industry's great contributions to our architectural history. The original artisan buildings had been abandoned as being not sufficiently versatile and incapable of housing the new machinery, and the iron-working industry was in need larger buildings. The very material that was manufactured was also to play a role in the development of these new structures: while the first bays were built using traditional techniques-wood for roofs and stone for the outer walls-after a few decades the industry had progressed far enough the enable iron to be used as the basic component in construction.

With the use of iron, the spans between pillars and load-bearing elements could be widened, new arrangements were found for the trusses that distributed the loads of the roof, weight was shed from the walls until they eventually became light enclosures in which the metal structure provided the necessary solidity, allowing window openings to be arranged more conveniently and with greater versatility and widened to provide more light. After iron, the spread of reinforced concrete gave a new functional and aesthetic dimension to the buildings.

Whatever the material used, though, the bay has always been the most common arrangement in the iron industry. Multi-storey factories were generally not favoured, as both the machinery and the raw material were so heavy that they would have created excessive loads-with a consequent increase in building costs-and greater difficulties in internal transport than in the bays where everything was on the same level. The multi-storey factory and other similar models were only used in response to the specific needs of certain industries.

There was no radical overnight transformation in building however. If we look at some of the main examples, we can see how these ideas gradually developed over time. The first factories, like the Vergarajaúregui, Resusta y Cía factory in Aretxabaleta, were built along traditional lines. Here, manufacture was carried out in two long two-storey wings, flanking the more prominent central building, which housed offices, general services and the administrator's house. Traditional materials-wood and stone-were the basic elements used. Indeed, if it were not for the size of the building and the original mill fall at the back, the building might well be mistaken for a private house or residence in the eclectic neo-regionalist style, so beloved of late nineteenth century architects. The La Cerrajera Guipuzcoana factory in Arrasate-Mondragón, which has since been demolished, was similar. It made extensive use of stone, and in both the techniques and the materials used it might well be taken for one of the traditional factory buildings of former times.

It was the creation and progressive enlargement of the large complexes, however, that was to lead to the development of a new architectural structure and a new formal language. One of the most interesting examples is the CAF plant in Beasain. The factory contains a wide range of bays, combining the single-storey model-such as the old boilershop-with seried bays, a good example of which can be seen in the assembly workshop. This has seven passageways with seven modules of terraced bays, covering a surface area of 155 x 100 metres. The foundry and modelling workshop is also magnificent, with an even more developed roof plan for each of the component modules. Additional light is provided by the large windows in the tympanum of the facade. In all cases, one of the striking features is precisely the serrated silhouette of the roof, which lends the entire building a certain unity, and although there are also cases of simple two-slope roofs, the most striking are the projecting lantern-shaped roofs, the serrated triangles of the assembly workshop and the shed, with its longitudinal skylights.

As well as these functional aspects, though, care has also been taken over the aesthetic features of the architecture. In the bays, doors and windows on plain walls, which were originally whitewashed all over, are framed by solid bricks in alternating colours. The play of horizontals and verticals in the facade is also highlighted with plain stripes running across the space and delimiting volumes. The original identifying signs for the bays and other areas, with their clear Modernist influence, are particularly interesting: they combine the company logo, the name or purpose of the bay and a large code letter in capitals (E for the mechanical area, F for assembly, L for foundry, etc).

CAF also contains another of the distinguishing features of these large metalworking complexes: internal organisation. The factory precinct was conceived as a unified industrial space divided into zones, with the basic routes for the movement of operators and materials arranged as rationally as possible. Inevitably, at CAF this organisation is further backed by the presence of an internal railway system.

This same rational language was used in the Patricio Echeverría factory, whose separate pavilions were also once connected by rail tracks. The complex has grown up along either side of the road leading into Legazpi and now contains elements dating from very different periods, ranging from the first decade of the twentieth century to the present day (HERRERAS and ZALDUA, 1997). Some remains can still be seen of the original plant, although these have been greatly remodelled, and old photographs show links with the decorative patterns of the CAF complex, such as the stripes and square columns dividing up the facades, the use of tiered ball-courts to act as screens, the highlighting of openings, and the tiered lighting at the front which seems to have been a feature of these early pavilions.

Later on, the firm's need to expand led to alterations in the decoration, and in line with the trends of the time, a much simpler language was adopted, with a predominance of brick, concrete and iron, combined in different ways in walls, frames, pillars, trusses and roofs.

The present office building displays a preference for bare brick walls, cut with regular openings and framed with arches. The large main entrance is delimited with a screen and crowned with a triple window, while the empty spaces are filled with the company's name and trademark. The other extreme in building formulas can be seen in the present foundry, where the great metal and concrete structure is enclosed simply with plate and corrugated parts, linking it directly to the industrial building style of the last quarter of the twentieth century.

Other examples of this combination of styles can be seen in Unión Cerrajera de Mondragón in Arrasate-Mondragón and the same company's premises in Bergara. In Arrasate-Mondragón part of the plant which was nearly a century old, and which included buildings and arrangements from various different eras, was recently torn down. The material legacy in Bergara, fortunately, has fared rather better although much of the rolling pavilion has gone, where a structure of latticework pillars and riveted girders supported the transverse cranes and the crownpost trusses. Here a type of rational "facadism" or concealment was used, with horizontal and vertical play in two colours, with frames and stripes, tiered screens to reinforce the lines and the inevitable clock, with the large rolling mill and the heating furnaces forming the most important feature in the space. The storage bay has survived, however, and has been intelligently converted into a sports complex, taking advantage of the versatility of the factory spaces, and so has the very interesting plate rolling workshop, built in 1926.

The entire space is designed as a single uninterrupted body, as its functions required. The long rectangular floor is covered with a twin-sloped roof with a projecting skylight, which aids ventilation. As a result, the shorter elevations are pronouncedly tiered, making them look like a Gothic church, with a particularly narrow central nave. The use of reinforced concrete in the structure has made it possible to leave wide open glass sides. The arrangement is repeated in the sides, where the particularly wide openings are framed in two superimposed registers, to which an aesthetic rhythm has been added by a pronounced wooden valance or small eave, forming a cresting arch.

This preference for the presence of natural light in the work area can also be seen in the Elma office and warehouse building in Arrasate-Mondragón, dating from 1924. This is an imposing rectangular block, divided into two bodies: one oblong in shape, with a projecting quadrangular tower occupying the angle. The facades are completely open, from the top down to the first floor, with large three-part windows, framed between square pillars decorated with trimmed plates in a Baroque style. The entire complex is crowned by a well-developed cornice projecting outwards, crowned by a solid moulded balustrade, from which small tiered pinnacles stick out at regular intervals, with a space for the company name. This enormous block is a clear example of the possibilities offered by the use of reinforced concrete, whose resistant framework allowed multi-storey factories to be built for this industry, especially in the specialist areas of processing and adjustment.

We can complete this brief summary of some of the most outstanding architectural elements by looking at the formulae used by the arms manufacturers of the lower Deba area. As we have seen, it was the tradition and the concentration of operators in those municipalities which led to the establishment of the first factories in the second half of the nineteenth century. Since they came from a dispersed manufacturing system, based on small units, and because this was precision work, the first examples-such as the early Orbea workshop-were simS.A.l bays, often built using traditional materials and techniques.

However, the proliferation and success of these arms manufacturers, especially during the first decade of the twentieth century, led to the expansion of the firms and the need for new spaces to work in. In this second phase, the most important examples were built in a rationalist style, which was rapidly tending towards functionalism: naked and often impersonal. The first conditioning factor they came up against was a lack of available space to build on: the problem of urban concentration, particularly in Eibar, was compounded even further by the narrow river valley. As a result, they were forced to build multi-storey factories, which allowed a better return on the investment in land, by doubling, trebling or even quadrupling the capacity, depending on the number of floors. This industry was also fortunate in that the material used in the factories was small and light.

As a result, workshops were built that fitted in perfectly with the urban landscape, and can only be distinguished from regular apartment blocks by the way the windows are grouped and by the size of the openings, which were generally larger in size, running either in series or opening right across the facade from one side to the other. Windows were framed with stripes while internally concrete structures were used and the block was fitted with stairwells and lifts for goods and people. As a result the factories fitted in well in the urban landscape. around the same time, other companies were setting up in the areas between the towns. They tended to huddle together and were often associated to the new metal industries, such as the first sewing machines (ALFA, Singer) which were to lead the way in the successful development of the small domestic appliances industry.

Indeed, the gradual improvement in living conditions from the beginning of the 1960s saw the rapid development of this industry, which became an ever more important element in the overall metallurgical panorama of Gipuzkoa. New compact factory complexes were built to meet the demand, half-way between the style used in the Lower Deba and the larger complexes we have described above. As the industry grew over the following decades, these plants gradually moved to modern industrial estates, where the metalwork has fitted in perfectly alongside a wide range of different industries, and the various companies are generally concentrated in anonymous series of pavilions, with metal now rubbing shoulders with modern plastic materials.

The development of the metalworking industry in Gipuzkoa is unquestionably one of the keys to understanding the history of the province and to explaining its present, and many traces of that development can still be seen in our landscape. On the site of an old forge a quiet industrial revolution took place: first the workshops and blast furnaces, and then the companies that led the industrial drive of the early twentieth century, companies which struggled and were transformed in the difficult years of the mid-century, and which in the 1980s finally moved to the new industrial estates. This pattern of different stages can be applied to many different sites in the province, and it gives provides a good explanation of the main features of the modern-day metallurgical industry: varied, modern, flexible and versatile, with a high level of capitalisation and efficiency. And although there are notable exceptions, the material legacy too tells the history of the process, born in the heat of simple charcoal-burning stone furnaces, and forged with sweat and "armpower".