The Municipality of Markstay-Warren lies within the Sudbury East area, located along the Highway 17 corridor between the City of Greater Sudbury and the City of North Bay. It was created in 1999 through the amalgamation of the political townships of Hagar, and Ratter and Dunnet, the geographic township of Awrey, and portions of the geographic townships of Hawley, Street, Loughrin and Henry. The three major settlements within the Municipality are the village of Markstay, the village of Hagar, and the village of Warren.