Montreal Olympic Stadium and surrounding structures, are but a few notable examples of the city's 20th-century architecture. Pavilions designed for the 1967 International and Universal Exposition, popularly known as Expo 67, featured a wide range of architectural designs. Though most pavilions were temporary structures, several have become landmarks, including Buckminster Fuller's geodesic dome U.S. Pavilion, now the Montreal Biosphere, and Moshe Safdie's striking Habitat 67 apartment complex. The Montreal Metro has public artwork by some of the biggest names in Quebec culture. In 2006 Montreal was named a UNESCO City of Design, only one of three design capitals of the world
Geodesic dome resists sun and weathering. Some form of internal flashing or caulking must be placed over the joints to prevent drafts. The 1963 Cinerama Dome was built from precast concrete hexagons and pentagons. Given the complicated geometry of the geodesic dome, dome builders rely on tables of strut lengths, or "chord factors". In "Geodesic Math and How to Use It", Hugh Kenner writes, "Tables of chord factors, containing as they do the essential design information for spherical systems, were for many years guarded like military secrets. As late as 1966, some 3"ν" icosa figures from "Popular Science Monthly" were all anyone