The Panama–Pacific International Exposition was a world's fair held in San Francisco, California, United States, from February 20 to December 4, 1915. Its stated purpose was to celebrate the completion of the Panama Canal, but it was widely seen in the city as an opportunity to showcase its recovery from the 1906 earthquake. The fair was constructed on a 636-acre (257-hectare) site along the northern shore, between the Presidio and Fort Mason, now known as the Marina District.

A world's fair, also known as a universal exhibition or an expo, is a large global exhibition designed to showcase the achievements of nations. These exhibitions vary in character and are held in different parts of the world at a specific site for a period of time, typically between three and six months.