Wellesley Island State Park is a 2,636-acre (10.67 km2) state park[2] located on Wellesley Island in the St. Lawrence River in the Town of Orleans in Jefferson County, New York. The park is divided into sections that are on different parts of the island. It has the largest camping complex in the Thousand Islands region,[1] including wilderness campsites on the banks of the St. Lawrence accessible only by foot or boat.