The “Estadio Olimpico” which is situated on the Cartuja Island, the former Expo-site in Seville, was opened to the public in May 1999. It is covered by a light cable supported membrane roof 25,000 m² in plan. The membrane oscillates between 44 upper and 44 lower radial cables which span between an outer stiff compression ring and an inner tension ring. The overall structural system, a spokes wheel roof, is similar to the roof of the “Gottlieb-Daimler-Stadion” in Stuttgart, Germany. The innovative feature introduced here is that, contrary to the Stuttgart roof, in Seville the membrane is actually a structural load bearing component. It connects and tensions the radial cables, thus giving the necessary tension and stiffness which the roof needs.