Although originally this building was commissioned by the Pirelli Company to be built on the site of the company's first factory, today the building is occupied by government offices. When completed, it was the tallest building in Europe at 127.1 meters (417 feet) and today it is still the tallest building in Milan. It is one of the few skyscrapers with a reinforced concrete structure--instead of the more typical frame of steel.
Although the glass curtain wall is typical of "modern" skyscrapers of this era, it abandoned the box form of office blocks. This elegant, much praised skyscraper has angled corners. Service and storage areas are behind the end walls leaving the central portions of the interior open.