“There are five North Poles: the North Geographical Pole, the absolute, fixed cap of the globe; the North Magnetic Pole, to which our compasses point, and which is not stationary but rambles at present through the Canadian Arctic; the North Geomagnetic Pole, which centres the earth's magnetic field and sits today over north-west Greenland; the Northern Pole of Inaccessibility, a magnificently named spot in the Arctic Ocean north of Alaska, which represents the point farthest in all directions from land (currently, 684 statute miles from the nearest coast); and there is even a Pole in the sky, the North Celestial Pole, the astronomical extension of a line drawn through the earth's axis which nearly - but not quite - hits Polaris.”