Check out this charming 1916 photo of beautifully dressed ladies and gentlemen eagerly waiting on the lawn to attend a concert during the Panama California Exposition! It's such a timeless and elegant scene. The Panama California Exposition held at 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.