Walden was a town in the Canadian province of Ontario, which existed from 1973 to 2000. Created as part of the Regional Municipality of Sudbury when regional government was introduced, the town was dissolved when the city of Greater Sudbury was incorporated on January 1, 2001. The name Walden continues to be informally used to designate the area.

The Regional Municipality of Sudbury was a regional municipality that existed in Ontario, Canada, from 1973 to 2000, and was primarily centred on the city of Sudbury. It served as an upper-tier level of municipal government, aggregating municipal services on a region-wide basis like the counties and regional municipalities of Southern Ontario, and was the only upper-tier municipal government ever created in Northern Ontario. The regional municipality was dissolved with the creation of the amalgamated city of Greater Sudbury on January 1, 2001.