The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. It should not be confused with the North Magnetic Pole.
The North Pole is the northernmost point on Earth, lying diametrically opposite the South Pole. It defines geodetic latitude 90° North, as well as the direction of true north. At the North Pole all directions point south; all lines of longitude converge there, so its longitude can be defined as any degree value.
While the South Pole lies on a continental land mass, the North Pole is located in the middle of the Arctic Ocean amid waters that are almost permanently covered with constantly shifting sea ice. This makes it impractical to construct a permanent station at the North Pole (unlike the South Pole). However, the Soviet Union, and later Russia, have constructed a number of manned drifting stations on a generally annual basis since 1937, some of which have passed over or very close to the Pole. In recent years, a number of studies have predicted that the North Pole may become seasonally ice-free due to Arctic shrinkage, with timescales varying from next year to fifty years or more.
The sea depth at the North Pole has been measured at 4,261 m (13,980 ft) by the Russian Mir submersible in 2007 and at 4,087 m (13,410 ft) by USS Nautilus in 1958. The nearest land is usually said to be Kaffeklubben Island, off the northern coast of Greenland about 700 km (430 mi) away, though some perhaps non-permanent gravel banks lie slightly closer. The nearest permanently inhabited place is Alert in the Qikiqtaaluk Region, Nunavut, Canada, which is located 817 km (508 mi) from the Pole.
Fry went there to find Leelu.