Route 107 starts east of Nashwaak Bridge travelling south-west crossing Route 148 and into Nashwaak Bridge.

From here, the route crosses the Nashwaak River before turning north-west and passing through Sutherland Siding.

From here, the route is known as "Irishtown Rd" as it enters the community of Nashwaak.

Through mostly uninhabited forest land, through Williamsburg then the railway siding of Napadogan as it passes Miramichi Lake then meets up and begins to follow the south bank of the Southwest Miramichi River as it passes Deersdale, to the community of Juniper.

The road now known as Route 107 was not fully completed until the late 1950s, when the section between Napadogan and Juniper opened.