Moscow 1980
This poster was designed by Wladimir Arsentjev, and features two running tracks that combine to form a structure/flame, sitting on top of which is a red star, the emblem of the Soviet Union. Restricted colour, symmetry, and strong design all help make this an iconic poster. However, it wasn't part of any broader branding for the Moscow Games, with other posters looking distinctly amateurish in comparison.