The Municipality of Metropolitan Toronto was an upper-tier level of municipal government in Ontario, Canada, from 1953 to 1998. It was made up of the old city of Toronto and numerous townships, towns and villages that surrounded Toronto, which were starting to urbanize rapidly after World War II. It was commonly referred to as "Metro Toronto" or "Metro".

York County is a historic county in Upper Canada, Canada West, and the Canadian province of Ontario. It was organized by the Upper Canada administration from the lands of the Toronto Purchase and others.