Expo 67 United States Pavilion Button, 1967

Expo 67, held in Montreal, Canada, was the most attended World's Fair of the 20th century. The United States pavilion, a 250-foot-diameter geodesic dome designed by visionary Buckminster Fuller and architect Shoji Sadao, remains the most iconic and fondly remembered of Fuller's built designs. This button implies that, even at the time, the design was recognizable without additional text needed.