CIAM founded

What it is

The Congrès Internationaux d'Architecture Moderne was founded in 1928 at the Château de La Sarraz in Switzerland, where architects including Le Corbusier and Sigfried Giedion gathered to set a common modernist agenda. Across its meetings it defined the city through four separated functions — dwelling, work, recreation and circulation — a doctrine later distilled in the Athens Charter. It promoted high-rise housing in open green space, zoning by use and rational, expert-led planning.

Why it matters

It institutionalised functionalist, zoning-based urbanism as an international movement, and its ideas drove the design of postwar housing estates and new towns across Europe, the Americas, Africa and Asia.

Plans it shaped

• Plan Obus for Algiers (unbuilt) (1931–1934)
• Amsterdam AUP (Algemene Uitbreidingsplan) (1935)
• Rome EUR (Esposizione Universale di Roma) (1937–)
• Rotterdam Basisplan (1946)
• Lima Plan Piloto (1949)
• Havana Plan Piloto (1955)
• Brasília Pilot Plan (1957–1960)
• Ville Radieuse (Radiant City) (1930–1935)
• Weissenhofsiedlung (Die Wohnung exhibition estate) (1927)
• Neues Frankfurt (New Frankfurt) — Römerstadt and the May Siedlungen (1925–1930)
• The Athens Charter (CIAM IV, the Functional City) (1933 (published 1943))
• Milyutin's Sotsgorod and the Magnitogorsk linear-city debates (1930)