The north wing of the City Hall was the original location of the Peterborough Public Library.

The library was built in the Beaux-Arts style by prominent local architect John E.

[2] The cornerstone was laid on December 1, 1950, by Leslie Frost, Premier of Ontario, and City Hall was officially opened in October 1951 by Charlotte Whitton, Mayor of Ottawa, and Mayor George Rowell Chamberlain of Peterborough, England.

The sandstone building is a late example of Beaux-Arts architecture inspired by the City Beautiful movement.

[3] The lobby features a marble terrazzo-tiled floor depicting a map of Peterborough County with brass inlay.