The Avus Grand Prix, 1935
Rosemeyer and Stuck for Auto Union (i.e. Audi), Nuvolari for Alfa Romeo, Bimotore and Fagioli for Merecedes-Benz and Farina for Maserati lining up at the starting grid.
Note the unusual soft canopy fixed on one of the Auto Union cars.
(via emrayfo)


