THE THOUSAND ISLANDS BRIDGE SYSTEM extends from Collins Landing near Alexandria Bay, New York to Ivy Lea near Gananoque, Ontario covering a distance of 8.5 miles and provides direct connection between US Interstate Rt. 81 and Canada Highway 401.

The crossing over the American channel of the St. Lawrence River from the mainland to Wellesley Island, consists of a suspension bridge of 800 ft. (main span), with an underclearance of 150 ft. above the river. The American span from abutment to abutment is 4500 ft.

The Canadian Crossing includes the 600 ft. continuous Warren Truss span connecting Hill Island to Constance Island. A steel arch of 348 ft. spans from Constance Island to Georgina Island. A suspension bridge of 750 ft. from Georgina Island to the Canadian mainland (Ontario) with the suspension span providing 120 ft. of underclearance above the river. The Canadian span from abutment to abutment is 3,330 ft.

The boundary at the International Rift, between Wellesley Island and Hill island, is bridged by two parallel 90 ft. rigid frame arched spans of reinforced concrete with masonry facing. Originally there was only one bridge at the boundary or International Rift, however increased traffic demanded twinning the crossing in 1959

Groundbreaking ceremonies were held at Collins Landing, New York, on April 30, 1937 with several thousand people on hand for this eventful occasion, both US and Canadian.

ENGINEERING: Robinson and Steinman of New York City were employed as consulting engineers by the Thousand Islands Bridge Authority. At the time, Dr. David Steinman was the foremost designer of bridges in the country and Dr., Holton Robinson was equally proficient on construction work. Monsaurat and Pratley of Montreal were employed as Canadian consultants. The original firm of Robinson and Steinman, now Steinman, Boynton, Gronquist and Birdsall are still the Authority's consulting engineers.