Postcard:Tower of Jewels and Court of the Universe at the Pan.-Pac.Int.Expo.San Francisco, 1915

The 1915 Panama-Pacific International Exposition, a world's fair celebrating the completion of the Panama Canal and the 400th anniversary of Vasco Nunez de Balboa's first glimpse of the Pacific Ocean, occurred on San Francisco's northern shore. Dozens of elaborate attractions and exotic buildings dotted the 635-acre fairgrounds, most of which were constructed of a mixture of plaster and burlap fiber. Fairgoers marveled at The Tower of Jewels, a soaring 435-foot structure covered in 102,000 Novagems-multicolored, faceted cut glass "jewels" mounted on brass hooks that danced in the breeze. When the fair ended, the buildings were torn down, with the exception of the Palace of Fine Arts. The palace was reconstructed in the 1960s, and today it is home to the Exploratorium, a well-known and innovative interactive science museum.