The Jackknife (or Jack-knife) Bascule Bridge is a bascule bridge that spans the Kaministiquia River at Thunder Bay, Ontario, Canada, to link the city to Mission Island, one of two islands in the Kaministiquia River delta. The bridge was built by the Canadian Pacific Railway between August 1910 and April 1913. The contractor for the abutments and piers was Alexander Charles Stewart (1867–1944).