Эльсмир: Самый северный остров Канады.

Island of the Arctic Archipelago in Nunavut, Canada

Ellesmere Island (; )|name=Cape Columbia is the most northerly point of land in Canada and one of the most northern points of land on the planet (the most northerly point of land on Earth is the nearby Kaffeklubben Island of Greenland). The Arctic Cordillera mountain system covers much of Ellesmere Island, making it the most mountainous in the Arctic Archipelago. More than one fifth of the island is protected as Quttinirpaaq National Park. In 2021, the population of Ellesmere Island was recorded at 144.|display=inline|name=Cape Sheridan) west to Cape Alert , including the Ward Hunt Ice Shelf. In 1906 Robert Peary led an expedition in northern Ellesmere Island, from Cape Sheridan along the coast to the western side of Nansen Sound (93°W). During Peary's expedition, the ice shelf was continuous; it has since been estimated to have covered .|name=Cape Columbia), is less than from the north pole, while its southern coasts at 77°N are well within the Arctic Circle. Ellesmere has the highest and longest mountain ranges in eastern North America and is the most mountainous island in the Arctic Archipelago. It has over half of the archipelago's ice cover, with ice caps and glaciers across 40% of its surface. Its extensive coastline includes some of the world's longest fiords. To the west, Ellesmere is separated from Axel Heiberg Island by Nansen and Eureka Sounds, the latter of which narrows to Devon Island is to the south across Jones Sound; at the west end of the sound, they are separated by North Kent Island and two channels which narrow to Greenland is to the east across Nares Strait; the strait narrows to at Cape Isabella on Smith Sound and further north narrows to at Robeson Channel. These channels and straits typically freeze over in winter, though winds and currents leave pockets of open water (temporary leads and persistent polynyas) in Nares Strait. To the north of Ellesmere is the Arctic Ocean, with Lincoln Sea to the northeast.

More than one fifth of the island is protected as Quttinirpaaq National Park (formerly Ellesmere Island National Park Reserve), which includes seven fjords and a variety of glaciers, as well as Lake Hazen, North America's largest lake north of the Arctic Circle. Barbeau Peak, the highest mountain in Nunavut is located in the British Empire Range on Ellesmere Island. The most northern mountain range in the world, the Challenger Mountains, is located in the northeast region of the island. The northern lobe of the island is called Grant Land. The Arctic willow is the only woody species to grow on Ellesmere Island. Nonetheless, there are archaeological remains of winter dwellings of both Independence and Thule cultures in the interior.

A paleolimnological study of algae in the sediments of shallow ponds on Cape Herschel (which faces Smith Sound on Ellesmere's eastern coast) found that the ponds had been permanent and relatively stable for several millennia until experiencing ecological changes associated with warming, beginning around 1850 and accelerating in the early 2000s. During the 23 year study period, an ecological threshold was crossed as several of the study ponds had completely desiccated while others had very reduced water levels. In addition, the wetlands surrounding the ponds were severely affected and dried vegetation could be easily burned. With the end of the Cold War and the advent of new technologies allowing for remote interpretation of data, the overwintering population has been reduced to 62 civilians and military personnel as of 2016.

Eureka (the third northernmost settlement in the world) consists of three areas: Eureka Aerodrome, which includes Fort Eureka (the quarters for military personnel maintaining the island's communications equipment); the Environment Canada Weather Station; and the Polar Environment Atmospheric Research Laboratory (PEARL), formerly the Arctic Stratospheric Ozone (AStrO) Observatory. Eureka has the lowest average annual temperature and least precipitation of any weather station in Canada.

Grise Fiord (Inuktitut: ᐊᐅᔪᐃᑦᑐᖅ, Romanized: Aujuittuq, lit. "place that never thaws") is an Inuit hamlet that, despite a population of only 144,