Old Stone Gate, Chicago Union Stockyards - View this location on map  From about 1879 to 1971, this triple-arched, rough-faced limestone gate was the main entrance to the Chicago Union Stockyards. The Stockyards, founded in 1865 to consolidate the many scattered stockyards in Chicago into an efficient unit, symbolized Chicago's role as a major meat-packing center. W. Exchange Avenue and South Peoria Street, Chicago, Illinois Historical |