The following text comes from the "City Hall and Insignia" page on the city website (archived) and explains the thinking behind the "three C" logo:
The three C's used in the City of Cambridge logo represent both the Corporation of the City of Cambridge (as an acronym 'CCC') and also the three founding communities of Galt, Preston and Hespeler. The amalgamation of these communities is illustrated in the interlocking design. The white space between the letters is representative of the exchange of ideas and culture and communication of desires of the three founding communities now being channeled into one community with common goals.News reports about the logo change:
The blue, green and gold 'Three C' logo is the informal symbolic device designed to represent the Corporation of the City of Cambridge on its letterhead paper and brochures.
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