Thousand Islands level year-round, and support at least two living trees. The Thousand Islands archipelago is located at the outlet of Lake Ontario at the head of the Saint Lawrence River. The region is bisected by the Canada–United States border and covers portions of Jefferson and St. Lawrence counties in the U.S. state of New York, in addition to parts of the United Counties of Leeds and Grenville and Frontenac County in the Canadian province of Ontario. Geologically, most of the islands are located where a branch of the Canadian Shield runs south across the river to join with the Adirondacks. The
Islands in the River Thames reeds, concrete, cement, wood or sheet piling. The islands are listed in order upstream from the sea. In the Oxford area the river splits into several streams across the floodplain, which create numerous islands. On the right bank a large island is created by Seacourt Stream, Botley Stream and Bulstake Stream, and there are smaller islands, including the large mainly built-up island now known as Osney, created by streams between Bulstake Stream and the Thames, including Osney Ditch. The Oxford suburbs of Grandpont and New Hinksey are on an island created by Bulstake Stream, Hinksey Stream and Weirs Mill Stream.