Expo 67, Montreal

Montreal hosted Expo 67, the 1967 World's Fair, marking the centennial of Canadian Confederation and becoming, by many measures, the most successful world's fair of the 20th century, drawing over 50 million visitors to man-made islands built in the Saint Lawrence River. The fair became an architectural showcase in its own right: Buckminster Fuller's 76-meter geodesic dome housed the United States pavilion, and Moshe Safdie's Habitat 67, an experimental complex of prefabricated modular concrete housing units stacked in an irregular, terraced arrangement, was built as a permanent pavilion demonstrating new approaches to affordable, high-density urban housing. Both structures became internationally influential built statements of 1960s architectural optimism about technology and prefabrication, and Habitat 67 remains an occupied apartment building in Montreal today.