The connecting links between the exhibition pavilions of the new trade fair in Milan are mostly covered by innovative steel-glass-structures which are very attractive from the architectural point of view. At the main entrance the ‘Logo’ arises: A double-curved free-formed surface, which ascends in the sky like a volcano. With a height of 37 m this structure will be recognized from afar as the new fair’s landmark. A 1.300 m long and 30 m wide free-formed glass roof, the so-called ‘Vela’, links the individual exhibition halls together along the main axis of the trade fair and absorbs the nearby Alps in its architectural design. Primary with the ‘Logo’ this paper specifies, besides the overall architectural concept, mainly the basic principles for the development of the grid topology and the characteristics of the structural system of the arbitrary curved free-formed surfaces.