introduced and annotated by interviews with some of the most famous architects in the world (including Kenzo Tange, Louis Kahn and Giovanni Michelucci) and other characters ( two designers of suspension bridges, an Indian engaged in construction of skyscrapers, the master of a barge motor Manhattan), are some of the most important achievements of steel in the world: from the Verrazano Bridge to the entrance of the port of New York to the Tagus in Lisbon, from the skyscrapers of Chicago Olympic stadium in Tokyo. Of particular interest today assume the amounts taken on top of the Twin Towers, then at an advanced stage of construction. The film, sponsored by Italsider, won the Grand Prize at the National Festival of Film Industry in 1973
