Picket Line on Public Square ID: 4611 | This file appears in: Cleveland Electric Illuminating Co. This May 1, 1957 picket line on Public Square in front of the 75 Building, and incomplete 55 Building, is visual evidence of the longest strike in C.E.I.'s history. The strike lasted from April 24 to May 7, 1957. | Date: May 1, 1957 | Source: Cleveland State University Michael Schwartz Library Special Collections Download Original File SourceCleveland State University Michael Schwartz Library Special CollectionsDateMay 1, 1957 "Picket Line on Public Square" appears in: Cleveland Electric Illuminating Co.