This image is an aerial view of the Thousand Islands Bridge, which connects Canada and the United States over the St. Lawrence River between Ontario and New York. It is distinctive by having three different kinds of bridge form: truss, arch and cable suspension.
The description states:
Aerial View of the Thousand Islands International Bridge — in the heart of the Thousand Islands — Ontario, Canada.
–In total there are five sections to the bridge, which was completed in 1937.
This image likely dates from the 1950s.