page_title: Timeline of Cincinnati
section_title: 20th century
hierarchical_section_title: Timeline of Cincinnati / 20th century
caption_attribution_description: Crosley Field Cincinnati 8/69 img076
context_page_description: The following is a timeline of the history of the city of Cincinnati, Ohio, USA.
context_section_description: 1900 - Population: 325,902.
  1902 - First reinforced concrete skyscraper - the Ingalls Building.
  1905 - U.S. premier of Mahler's Symphony No. 5.
  1906 - First university to offer cooperative education, University of Cincinnati.
  1909 - Evening School for Foreigners opens.
  1911 - Mount Airy Forest established.
  1912 - Labor Advocate newspaper begins publication.
  In 1912, the Cincinnati Reds opened a new steel-and-concrete ballpark, Redland Field (later to be known as Crosley Field). 
  1914 - Martha, the last passenger pigeon, dies at the Cincinnati Zoo.
  1916 - 9th Street YMCA opens.
  1920 - Population: 401,247.
  1926 - Cincinnati, Hamilton and Dayton Railway (1926–1930) in operation.
  1928 - LeBlond Aircraft Engine Corporation established.
  1930 - Population: 451,160 
  1930 - Cincinnati and Lake Erie Railroad in operation.
  1933 - Cincinnati Union Terminal opens.
  1937 - Ohio River flood of 1937
  1940 - Population: 455,610 
  1950 - Population:503,998 
  1951 - Last line of the Cincinnati streetcar system is abandoned.
  1952 - First heart-lung machine- makes open heart surgery possible. Developed at Cincinnati Children's Hospital Medical Center.
  1954 - First licensed public television station, WCET. 
  1960 - Population: 502,550.
  1967 - Race riot in Avondale.
  1968 - Riot in Avondale following the assassination of Martin Luther King.
  1977 - National Rifle Association convention held in city.
  1978 - Great Blizzard of 1978
  1979 - 1979 The Who concert disaster
  1983 - Air Canada Flight 797 accident
  1987 - Sister city relationship established with Munich, Germany.
  1988 - Sister city relationships established with Gifu, Gifu, Japan and Liuzhou, China.
  1989 - Sister city relationship established with Kharkiv, Ukraine.
  1990
  Cincinnati Museum Center at Union Terminal opens.
  Cincinnati History Museum opens.
  Population: 364,040.
  Sister city relationship established with Harare, Zimbabwe.
  1991 - Sister city relationship established with Nancy, France.
  1994 - Sister city relationship established with New Taipei, Taiwan.
  1998 - City website online (approximate date).
  1999 - April 1999 Cincinnati tornado
caption: The Reds played at Crosley Field, pictured here in 1969, from 1912 to 1970.
exif: {}