Wellesley Island (formerly Wells Island) is an island in the St. Lawrence River at the international boundary of the United States of America and Canada. It is one of the large Thousand Islands in the river.

The island is in Jefferson County, New York. Part of Wellesley Island is the Town of Orleans and the other part is the Town of Alexandria.

Geography

The location is at the west end of the St. Lawrence. The southeast peninsula of the island is separated from the Village of Alexandria Bay by the American Narrows. The island has a narrow central section.

Wellesley Island is traversed by Interstate Highway 81 to the Port of Entry located on the northeastern part of the island, adjacent to the Thousand Islands International Bridge, connecting the United States and Canada. Routes 100 and 191 also are on the island.

Geographic features

• American Narrows -- the branch of the St. Lawrence River passing to the south of Wellesley Island.
• Barnett Marsh -- A swamp in the south part of the island.
• Crow Island -- an small island off the north shore.
• Densmore Bay -- A bay on the south shore of the southeast peninsula.
• Eel Bay -- A large bay between Wellesley Island and Grindstone Island.
• Grenell Isle -- A smaller island southwest of Wellesley Island.
• Lake of the Isles -- A body of water connected to the St. Lawrence River, lying between the northeast and southeast peninsulas.
• Manhattan Group -- A cluster of small islands northeast of Wellesley Island.
• Murray Island -- A smaller island southwest of Wellesley Island.
• South Bay -- A bay on the southeast part of the island.

Communities on the Island

• Collins Landing
• Grandview
• Moore Landing
• Fineview
• Saint Lawrence Park
• Thousand Islands
• Westminster Park

Parks on the island

• Wellesley Island State Park -- In several locations on the island.
• Dewolf Point State Park -- On the northeast peninsula.
• Mary Island State Park -- At the tip of the southeast peninsula.