It was built in Nessonvaux (Trooz), in Belgium an assembler of cars called Imperia (1928-1958). Note that the Belgian factory had this idea (of building a test track) well ahead of the Italians and inaugurated in 1928, with a 1km circuit.
The Imperia before finishing 10 years later, on 48 mounted under license Standard Vanguards and the Adlers. We must also remember that in 37 just before the Great War, the chief engineer Louis de Monge and Ettore Bugatti made the mythical race car Bugatti 100P. But … we … falls between the factory and the track was in a hole almost at street level!
Between 1900 and 1950 Imperia wrote one of the most beautiful pages in the Belgian automotive history. The brand achieved both commercial and sporting high level peaks. In addition to great sales Imperia also recorded resounding successes in various international competitions on the road and the racetrack. With its own circuit around the factory Imperia evinced courage and desire for innovation during his 50-year existence. The factory is now closed, the halls are used for other purposes