Aberdeen Avenue is a Lower City minor arterial road in Hamilton, Ontario, Canada. It starts off just west of Longwood Road South and east of Highway 403 as a two-way thoroughfare up to Queen Street South, where it then switches over to a one-way collector road (eastbound) to Bay Street South and then to another two-way section from Bay Street to James Mountain Road, a mountain-access road in the city near the base of the Niagara Escarpment (mountain).