The steel structure is thrown across the Ebro River and simultaneously serves as a pedestrian bridge, an entrance pavilion for the entire Expo complex and an exhibition hall. Its shape demonstrates one of the strengths of Hadid's talent: the ability to fill a building with unstoppable dynamics, smooth, fluid energy, which is usually characteristic of liquid media, rather than the completely traditional solid materials that an architect uses for his work. This solution is especially well combined with the main "subject" of the exhibition in Zaragoza - the element of water.
The slogan of Expo-2008 is “Water for Life”, and the exposition in the Hadid building acquaints visitors with its most acute aspect: the need for rational use of water in conditions of its shortage in many regions of the planet. Moreover, an example of such difficulties is very close: the Ebro River has already become the cause of discord between Zaragoza and Barcelona. In the capital of Catalonia, water shortages may soon lead to the introduction of daily consumption rates, and it needs to divert some of the water from the Ebro to improve the situation, but Zaragoza, in which summer temperatures usually stay at 40 C, does not want to share a single drop.
But the main attention is drawn not by the exhibits, but by the magnificent exhibition pavilion itself. The bridge consists of four modules-compartments, whose shape is generated based on the motif of a rhombic section. This technique made it possible to make the structure as stable as possible, as well as to save building material.
One narrow and long module (185 m) leads from the right bank to the island in the middle of the river along a slightly curved trajectory, and from there to the shore of the Expo there are three parallel compartments, each about 85 m long. They support each other and also rest on the central the abutment of the bridge, buried to a level of 68 m - a record for Spain.
Each of the modules contains a separate exhibition hall inside, differing in the lighting scenario and the degree of openness to the external space.
The shell of the bridge is made on the principle of shark scales (again the theme of water) "tile": its individual elements are freely fixed on the rods and can rotate, either opening a wide opening outward, then reducing it to a gap. Thus, the perception of the inner space of the bridge by visitors will depend on various atmospheric phenomena: from the wind of the tramontana or the bright sun of Zaragoza.
