The Saint Lawrence River splits the United States and Canada into a granite-strewn labyrinth known as the Thousand Islands. Deer Island sits on the American side of the international boundary, roughly two miles downstream from Alexandria Bay, New York. Freight vessels traversing the St Lawrence Seaway geography pass through the deep shipping channel just south of the island, their wakes lapping against its rocky northern and southern points.
Unlike nearby tourist landmarks such as Boldt Castle on Heart Island or Singer Castle on Dark Island, Deer Island maintains no public welcome center. It spans roughly 40.5 acres, thick with white pine, hemlock, and oak. Boaters navigating the regional shoals often pass within several hundred yards of its granite shoreline without recognizing its significance. The island blends seamlessly into the surrounding cluster of private Upstate New York islands that house seasonal family camps and century-old boathouses.
