Which 1876 Philadelphia event was the first official world’s fair held in the United States?

The Centennial Exposition was the first official world’s fair held in the United States.

Officially called the International Exhibition of Arts, Manufactures, and Products of the Soil and Mine, it took place in Philadelphia’s Fairmount Park from May 10 to November 10, 1876. The exposition celebrated the centennial of the Declaration of Independence and presented American industry, science, agriculture, and culture to an international audience.

Nearly 10 million visitors attended, and 37 countries participated. Exhibits introduced or popularized technologies and products including the telephone, sewing machines, and typewriters. Memorial Hall became one of the fair’s best-known surviving buildings.

The event is sometimes confused with later American world’s fairs, especially Chicago’s 1893 World’s Columbian Exposition. Philadelphia’s 1876 fair came earlier and was specifically organized around the nation’s 100th anniversary.