Wonder and experiment: 15 pavilions that made history

The Royal Exhibition Building was built for the Melbourne International Exhibition of 1880, in line with the spirit of the international exhibition movement of the 19th century which aimed to promote innovation through industrialisation and international trade. The building, made of brick, wood, steel and slate, combines elements of the Byzantine, Romanesque, Lombard and Italian Renaissance styles. The complex is still in use as an exhibition and event centre, and is a popular tourist destination in the city.

The building was built as an exhibition space for Secessionist artists and soon became one of the most vibrant cultural centres of the time. The cubic, rigorous and almost windowless volume is dominated by the majestic, perforated dome, composed of thousands of laurel leaves (in honour of Apollo, God of the arts) in gold-plated copper, which stands out sharply against the immaculate surfaces. The building is still an exhibition centre today.

The imposing complex, a symbol of the Belle Époque, was built for the 1900 Universal Exhibition in Paris. The steel and glass structure features a majestic façade decorated with Ionic columns and gigantic bronze statues. Throughout the 20th century, the Grand Palais hosted events, fairs and exhibitions, and even today art exhibitions of major importance are held in the Galeries Nationales du Grand Palais. On the south-west side there is the Palais de la Découverte, a museum opened in 1937 and dedicated to science. The restaurant amidst the imperial columns offers a pleasant break in a radiant, aulic atmosphere.

The Glaspavillon was realised for the Deutscher Werkbund exhibition in Cologne, which was aimed at "ennobling" industrial manufacture and reducing the very strong divide, at that time, between architecture and the applied arts through the realization of buildings with a marked craftsmanship quality. The building, with a central plan and topped by a dome, consisted of a reinforced concrete load-bearing structure, on which a rhomboid mesh grid structure in a double layer was set: it was covered on the outside by reflective glass and on the inside by polychrome relief glass tiles. The building was short-termed: it closed soon after its opening due to Germany's entry into World War I. Its reinforced concrete structure survived the war and was intended for a short time to house still usable exhibition materials  before being demolished.

The temporary pavilion was built for the International Exhibition of Decorative Arts in Paris in 1925, as a full-scale prototype of a standardised dwelling composed of mass-produced elements. The building was conceived as a modular prototype cell to be repeated at the urban scale in the so-called immeuble-villas, with the aim of satisfying housing needs through quick, affordable but qualitative solutions.  The original pavilion was dismantled but, in 1977, a true replica was rebuilt in Bologna by architects Giuliano Gresleri and José Oubrerie: located near the exhibition complex designed by Kenzō Tange, the building is used as an exhibition space.

The work, realised for the Exposition des Arts Décoratifs in Paris, was conceived as the visiting card of Russian Constructivism in Europe. The building was characterised by a rectangular layout and a wood and glass structure; the volume was deconstructed into two triangular prisms, separated by a carving occupied by the staircase-bridge, on which sloping roof panels intersected. The centrepiece of the exterior space was the tower that supported the CCCP inscription.

Specially designed and constructed for the 1929 World's Fair in Barcelona, the iconic building expresses some of the fundamentals of Mies van der Rohe's thinking: from the open plan to the rigorous structural grid, to the use of high-quality materials, to the continuity between exterior and interior. The building is characterised by a clear orthogonal layout and is covered by a flat roof supported by slender cruciform pillars, that seems to float in the air. On the outside, the building's ethereal image is reflected in the two water pools: in the smaller one, Georg Kolbe's bronze sculpture ("Der Morgen") emerges from the water as lightly as the building stands on its travertine podium. Inside, fine materials (green marble, travertine, onyx) enhance the aulic and a-temporal character of the space. The structure, conceived as temporary, was demolished after the event and rebuilt philologically between 1983 and 1986. Today it hosts exhibitions and art installations and is the venue for the prestigious EU Mies Award.

In the 1960s and 1970s, the Zagreb Fair was one of the largest fairs in the world, a point of convergence of very different political ideologies and economic and cultural systems, especially during the Cold War. Out of the original 40 pavilions, only a third is used today: many have long since been put to other uses, or demolished, or are vacant. Among the most valuable, the listed Pavilion 40 stands out, built in 1956 in only five months, and characterised by a Brutalist design, recognisable in its sculptural volume and its massive exposed concrete structure.

Designed by Le Corbusier and the Greek engineer-musician Iannis Xenakis for the Brussels Expo of 1958, the reinforced concrete pavilion consisted of a group of nine hyperbolic paraboloids and housed the installation "Le poème électronique", consisting of a combination of lights, projections and music (composed by E. Varèse and Xenakis himself) and celebrating the new electronic age. The building was demolished in 1959.

The pavilion of Norway, Sweden and Finland at the Giardini of the Venice Biennale brings the poetics of light and the symbiotic relationship with Nature (typical of the Scandinavian countries) to the Venetian Lagoon. The rectangular building has no structural elements interrupting the space and is covered by a flat structure with a double level of reinforced concrete beams. The lattice formed by the overlapping beams allows the foliage of three plane trees to filter through; their trunks cross the volume, becoming an integral part of the building. Light reverberates widely on the diaphanous and essential surfaces, accentuated by the material choices: from concrete mixed with white cement, light sand and marble dust, to the large glass surfaces.

The structure was originally built as the US pavilion for 1967 Expo. The geodesic dome, Buckminster Fuller's signature shape, generated by an intricate network of steel tubes, is still an iconic landmark in the urban landscape. Today, the complex houses an environmental museum.

MVRDV's project developed a proposal for the theme "Holland Creates Space", revealing the potential of a country that has always faced land scarcity. The work took the form of an autonomous ecosystem with its own natural cycles, in which six typical Dutch landscapes (including a forest on the third floor) were stacked in a tower building. After twenty years of disuse, MVRDV's redevelopment project provided for the conversion of the exhibition pavilion into an office building with co-working spaces.

In Kensington Gardens, the Serpentine Galleries (Serpentine and Sackler Galleries) promote exhibitions of contemporary art and architecture of international relevance. Since 2000, each year the Serpentine Gallery has been commissioning a temporary summer pavilion from a renowned architect: each pavilion is completed within six months and installed on the Gallery's lawn for three months. Herzog & de Meuron and Ai Weiwei, authors of the Serpentine's twelfth Summer Pavilion, carried out an operation of modern archaeology, digging 5 metres below ground to reveal the remains of the eleven previous pavilions, on which the load-bearing elements of the new architecture were built. A flat roof, suspended a few metres above the turf, protected the "excavation": while the intrados was covered with cork, the extrados was covered with a thin surface of water that created reflections between the earth and the sky.

The Expo 2020 area is set to become a multifunctional district, as the event is over, by the end of 2021, in which many pavilions are being preserved. Among these, Alif stands out, the Mobility Pavilion, named after the first Arabic letter and, in extended form, meaning "beginning" (the beginning of a future based on tools and systems to facilitate and increase the quality of life): with its sinuous forms and shell clad in stainless steel sheets interspersed with curvilinear bands of glass, it evokes the idea of movement itself. The pavilion, distributed over five floors above ground and two underground, was designed with scrupulous attention to sustainability, from the self-shading conformation to the photovoltaic system, to the reflective shell.