The boundary between the U.S. and Canada crosses through both Lake Erie and Lake Ontario, with the two lakes shared by both countries.

The boundary between the United States and Canada crosses through Lake Erie and Lake Ontario, two of the five Great Lakes. These lakes form part of the border between the two countries, with Canada to the north and the U.S. to the south. Lake Erie, located to the west, and Lake Ontario, to the east, are significant bodies of water that provide important shipping routes, recreational opportunities, and vital ecosystems. The shared borders across these lakes highlight the close geographical and economic relationship between the U.S. and Canada, making them key areas for both international trade and tourism.