Canal Lake Concrete Arch Bridge is an arch bridge in Ontario, Canada, spanning a portion of Canal Lake on the Trent–Severn Waterway between Balsam Lake and Lake Simcoe. It is north-northeast from the town of Bolsover. The closed spandrel bridge is the earliest-known bridge in Canada to be constructed using reinforced concrete, and is based on a modified Melan System of bridge reinforcement. In 1988, it was designated a National Historic Site of Canada for representing a transitional period in bridge construction and a milestone in civil engineering in Canada.