Fiat test track on the roof of the Lingotto Building, Turin, 1929

 

The building was inaugurated in 1923 and housed a car factory -- the World's largest at the time -- for Italian automotive company Fiat. Today it houses the administrative headquarters of the manufacturer and a multipurpose centre.  The roof race track is 1.5 km long. It is no longer used, but it is still there and can be visited.

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