A Brief History of World's Fairs

San Francisco, 1915: Night Bright
Though it was ostensibly dedicated to the completion of the Panama Canal, the Panama-Pacific International Exposition was regarded as something much more: its opening in 1915 was heralded as a sign that San Francisco, which had been virtually destroyed in the earthquake and fire of 1906, had returned to life. The centerpiece of the fair was the Tower of Jewels, a 433-ft.-tall (132 m) structure adorned with more than 100,000 Austrian glass fragments called nova gems. In hues ranging from yellow to aquamarine, the gems glittered in the sunlight by day and were illuminated by floodlights and spotlights at night.

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