The Municipality of Greenstone is located along Trans-Canada Highway 11 in Northwestern Ontario, Canada 300km northeast of the City of Thunder Bay. Greenstone is located in the District of Thunder Bay and has an area of 3,172 sq km (1224 sq mi) making it one of the largest municipalities in Canada.
Greenstone was created on January 1st, 2001 by the amalgamation of the former municipalities of the Town of Geraldton, the Town of Longlac, the Township of Nakina and the Township of Beardmore, and an extensive area of unincorporated territory including numerous settlement areas such as Caramat, Jellicoe, MacDiarmid, and Orient Bay. First Nation communities within Greenstone municipal boundaries are Long Lake 58, Lake Nipigon Ojibway, Rocky Bay and Sandy Point, while Aroland and Ginoogaming First Nation Nations are situated just outside the Municipality, adjacent to the wards of Nakina and Longlac respectively.