[3][4] Highway 137 begins at the U.S. border crossing between Wellesley and Hill Islands, where it continues as south as I-81 towards Syracuse, New York.

After leaving the toll plaza and passing the duty free stores, the route curves northeast where it travels past the Thousand Islands Tower observation deck before turning north.

The geography surrounding the entire route features large rock outcroppings of the Frontenac Arch in the Canadian Shield through which the highway passes.

[6] The Thousand Islands Bridge system was opened in a ceremony on August 18, 1938 by Canadian prime minister William Lyon Mackenzie King and American president Franklin D. Roosevelt.

[7] The new bridge approach included an interchange with the St. Lawrence River Road, known today as the Thousand Islands Parkway, but it was not numbered.