Considering he is both an architect and a structural engineer, it is not surprising that Santiago Calatrava considers the professions inextricably intertwined. "There is a symbiosis between architecture and engineering," says Calatrava. "Looking at architects and engineers as separate disciplines is a convention and a new thing," says the designer for the $2.2-billion World Trade Center Transportation Hub in lower Manhattan.
Calatrava considers the separation unnaturala consequence of the evolution of the profession, related to the recent development of specialty consultants. With that outlook, it is also not surprising that the architecture is the structure and vice versa in most of Calatrava's buildings. The two public halls of the WTC hubthe icon reminiscent of a dove and another space, just below grade, with undulating concrete archesare no exceptions.