Driver Erndtmann and his mechanic Blouverstein June 1914 testing an Opel racecar. This was in preparation for the ACF (Automobile Club de France) Grand Prix to be held on July 4th in Lyon, France.

"The 1914 race at Lyon was considered one of the greatest Grand Prix races ever. 37 cars from 13 manufacturers in 6 different countries competed and after 7 hours, German Christian Lautenschlager won in a Mercedes."

Image Source : Bibliothèque nationale de France, département Estampes et photographie, EI-13 (366)

Text source: http://www.f1-grandprixhistory.net/France.html