The maritime boundary between Canada and the Danish autonomous territory of Greenland is the longest in the world at 2,139 nautical miles. It stretches from the North Atlantic Ocean in the south to the Arctic Ocean in the north. The boundary was initially established in 1973, revised in 2004 and extended in 2022. This all-purpose maritime boundary divides the territorial seas, continental shelves, exclusive economic zones and extended continental shelf claims of the Parties.

Tartupaluk, or Hans Island, a small uninhabited territory of less than 1.3 square kilometers in area, lies in the waters east of Canada’s Ellesmere Island and interrupts the maritime boundary before reaching the Lincoln Sea in the Arctic. Prior to 2022, Canada and Denmark disputed the sovereignty of Hans Island. As part of the most recent Agreement, the two States defined a 1.23 kilometer (0.76 mile) land boundary, which now defines each Parties’ sovereign territory, thus resolving the decades-old dispute.

Canada and Denmark also share a land boundary.