L'Avenue Nicolas II, Exposition Universelle, Paris, 1900 (b/w photo)

The Exposition Universelle of 1900 was a world's fair held in Paris, France, from 15 April to 12 November 1900, to celebrate the achievements of the past century and to accelerate development into the next. The style that was universally present in the Exposition was Art Nouveau. The fair displayed, in view of over 50 million people, many machines, inventions, and architecture that are now (nearly) universally known, including; escalators, the Eiffel Tower, Ferris wheels, Russian Nesting Dolls, Campbell's Soup, Diesel engines, talking films, and the Telegraphone (the precursor to modern-day sound recording).