The Thousand Islands Bridge System extends from Collins Landing near Alexandria Bay, NY to Ivy Lea near Gananoque, Ontario covering a distance of 8.5 miles. The bridge system provides a direct connection between US Interstate RT 81 and Canada highway 401. the Bridge crosses the American Channel of the St. Lawrence River from the mainland to Wellesley Island with an 800 ft suspension bridge. The underclearance is 150 ft above the river. The 600 ft Canadian crossing, the Warren Truss span connects Hill Island with Constance Island. A suspension bridge of 750ft from Georgia Island to the Canadian mainland has 120 ft of underclearance above the St. Lawrence River.