Factory workers race on the roof of the Fiat factory in Turin, Italy (1923)
The Lingotto building is a massive half-kilometer long reinforced concrete structure, five stories tall, that once housed the largest and most modern car manufacturing plant in Europe. Located in the heart of the city, Fiat made clever use of the available real estate by building a test track on the rooftop.
Built between 1916 and 1923, it was one of the first buildings of its size to rely heavily on reinforced concrete. Space constraints imposed by the railway lines nearby, forced architect Giacomo Mattè-Trucco to develop a building that went vertically up. Production started at the ground floor and continued sequentially up through the upper floors. As each floor passed, the cars approached their final shape until they emerged as a finished product at a simple yet ingenious looped rooftop test track with two banked turns.