1970 or 71 in rural France. Camped in a VW bus on the side of a back road. Looked out the off road window and saw a rotating disc of considerable size with white and red lights on it's rim. WTH???

Turned out to be a reflection in the window of cars driving around a long curve on a provincial highway across the valley from us....with very even spacing between vehicles. Had my hair standing on end. Took more than a few minutes to figure it out. No, it wasn't the 50 centime wine we had with supper.