Route 185 is part of the Trans-Canada Highway.

At present, Route 185 is a 2-lane highway with passing lanes.

Often cited as one of the most dangerous highways in Canada, it is being upgraded to Autoroute standards and will be a 4-lane restricted-access freeway, assuming and extending the existing Autoroute 85 designation.

Once this upgrade is completed, it will close the last gap in a continuous freeway section of the Trans-Canada between Renfrew, Ontario, and Lower South River, Nova Scotia - a length of over 1,500 km (900 mi), and for an even longer interprovincial freeway route between Windsor, Ontario and Halifax, Nova Scotia - a length of about 2,150 km (1,300 mi), roughly playing the same role that the old Quebec Route 2 (which Route 185 was formerly part of) played before its renumbering into several roads in the early-1970s.

The opening of the remaining portion in 2026 will also mark the end of Route 185.