Since 1925, Canada has claimed the portion of the Arctic between 60° and 141°W longitude,[89] but this claim is not universally recognized. Canada is home to the world's northernmost settlement, Canadian Forces Station Alert, on the northern tip of Ellesmere Island – latitude 82.5°N – which lies 817 kilometres (508 mi) from the North Pole.[90] Much of the Canadian Arctic is covered by ice and permafrost. Canada has the longest coastline in the world, with a total length of 202,080 kilometres (125,570 mi);[88] additionally, its border with the United States is the world's longest land border, stretching 8,891 kilometres (5,525 mi).[91]