What is the Canada-Greenland border?

The Canada-Greenland border is the maritime boundary between Canadian territory (Nunavut) and Greenland, an autonomous Danish territory. The boundary runs about 2,685 kilometres through Nares Strait (between Ellesmere Island and Greenland), Baffin Bay, and Davis Strait. Until June 14, 2022, the boundary was Canada's only international land border excluding the United States, running through Hans Island (Tartupaluk) in Nares Strait, where the border had been disputed for decades.

The maritime boundary was established by the Canada-Denmark Maritime Boundary Treaty of December 17, 1973 (ratified March 13, 1974), one of the longest maritime boundaries in the world. The treaty traced 127 turning points along the median line between the two coasts. The 1973 treaty deliberately did not address Hans Island, a small (1.3 square kilometre) uninhabited rock in the centre of the Kennedy Channel of Nares Strait. Both Canada and Denmark claimed the island, and a decades-long 'whisky war' developed in which alternating Canadian and Danish naval visits would replace the previous nation's flag and leave behind a bottle of Canadian Club or schnapps as a friendly territorial marker.

Hans Island was settled by the Hans Island Treaty signed by foreign ministers Melanie Joly and Jeppe Kofod on June 14, 2022. The treaty divides the island roughly down its middle along a natural ravine, giving Canada (Nunavut) the western section of about 0.6 square kilometres and Denmark (Greenland) the eastern section of about 0.7 square kilometres. The treaty resolves the world's only land-border dispute that had been outstanding without violence and creates the only land border between Canada and any country other than the United States. The Inuit communities of Grise Fiord on the Canadian side and Qaanaaq on the Greenlandic side have unrestricted access to both sides under the treaty.

The Canada-Greenland border has growing strategic and environmental importance. Climate change is opening the Northwest Passage and reducing Arctic sea ice, with implications for shipping, fisheries, and resource extraction. The Pikialasorsuaq (the North Water Polynya) between Ellesmere Island and northwestern Greenland is one of the most biologically productive Arctic marine ecosystems and is the focus of joint Canadian-Danish-Greenlandic-Inuit conservation discussions. The Pikialasorsuaq Commission (a joint Inuit body) has proposed an Inuit-led management area for the polynya. Federal Canadian Arctic sovereignty includes the expanded Canadian Coast Guard presence, the Arctic and Offshore Patrol Ships of the Royal Canadian Navy, and the modernised North American Aerospace Defense Command (NORAD).