Calumet Island sits across from Clayton NY on the north side of the shipping channel. The island formerly featured one of the earliest examples of the large castles built in the Thousand Islands region during the late 19th and early 20th centuries, of which Boldt Castle is a surviving example. It is the home of the Calumet. In the 1960s and early 1970s, Calumet Island was the site of the Calumet Island Marina, and included a restaurant and bar as well. As of 2011, the island is owned by the Rawson family who use it for summer holidays.