Construction photo of the Varied Industries Building. Construction began in 1911 for the Panama California Exposition which was held in Balboa Park in San Diego between January 1, 1915, and January 1, 1917. The exposition celebrated the opening of the Panama Canal, and was meant to tout San Diego as the first U.S. port of call for ships traveling north after passing westward through the canal. This is a view of a building under construction that exhibited various industries.