The Louisiana Purchase Exposition, informally known as the Saint Louis World's Fair, was an international exposition held in St. Louis, Missouri in 1904.
A number of foods are claimed to have been invented at the fair. The most popular claim is that the waffle-style ice cream cone was invented and first sold during the fair. However, it is widely believed that it was not invented at the Fair, but instead, it was popularized at the Fair. Other claims are more dubious, including the hamburger and hot dog (both traditional American foods), peanut butter, iced tea, and cotton candy. It is more likely, however, that these food items were first introduced to mass audiences and popularized by the fair. Dr Pepper and Puffed Wheat cereal were first introduced to a national audience at the fair.
Iced tea had been available for a few years prior to the fair, but it was popularized at the fair.