Pole of inaccessibility

For the Antarctic research station, see Pole of Inaccessibility (Antarctic research station).

Map of distance to the nearest coastline (including oceanic islands, but not lakes) with red spots marking the poles of inaccessibility of main landmasses, Great Britain, and the Iberian Peninsula. Thin isolines are 250 km (160 mi) apart; thick lines 1,000 km (620 mi). Mollweide projection.

A pole of inaccessibility marks a location that is the most challenging to reach owing to its remoteness from geographical features that could provide access. Often it refers to the most distant point from the coastline. The term describes a geographic construct, not an actual physical phenomenon. Subject to varying definitions, it is of interest mostly to explorers and adventurers.

Northern pole of inaccessibility

Northern pole of inaccessibility

The northern pole of inaccessibility, sometimes known as the Arctic pole of inaccessibility, or just Arctic pole, is located on the Arctic Ocean pack ice at a distance farthest from any land mass. Long thought to lie at , it was 661 km (411 mi) from the North Pole, 1,453 km (903 mi) north of Barrow, Alaska, and equidistant from the three closest landmasses, Ellesmere Island, Franz-Josef Land, and the New Siberian Islands, 1,094 km (680 mi) away. This follows from simple geometry, where three points suffice to define a circle; the pole of inaccessibility is then defined as the center of the largest circle that can be drawn within the Arctic ocean without including any land.

It was first crossed by Sir Hubert Wilkins, who flew by aircraft in 1927; in 1958, a Soviet icebreaker reached this point. Owing to the constant motion of the pack ice, no permanent structure can exist at that pole.

According to some reports, the first person to reach the spot on foot was Sir Wally Herbert, who arrived by dogsled in 1968. Other reports speak of this Pole as being still unconquered as of explorer Jim McNeill's unsuccessful attempt in 2006. According to McNeill, Herbert did not quite make the Pole, whose position has also now been more accurately determined.

A recent review of satellite cartography revealed that the pole actually lies at , 214 km (133 mi) away from the previous location, 1,008 km (626 mi) from Ellesmere, Komsomolets and Genriyetta Islands.

Southern pole of inaccessibility

Southern pole of inaccessibility

The old Soviet Pole of Inaccessibility Station, revisited by Team N2i on 19 January 2007

The southern pole of inaccessibility is the point on the Antarctic continent most distant from the Southern Ocean. A variety of coordinate locations have been given for this pole. The discrepancies are due to the question of whether the "coast" is measured to the grounding line or to the edges of ice shelves, the difficulty of determining the location of the "solid" coastline, the movement of ice sheets and improvements in the accuracy of survey data over the years, as well as possible typographical errors. The pole of inaccessibility commonly refers to the site of the Soviet Union research station mentioned below, which lies at (though some sources give ). This lies 878 km (546 mi) from the South Pole, at an elevation of 3,718 m (12,198 ft). Using different criteria, the Scott Polar Research Institute locates this pole at .

According to ThePoles.com, the point farthest from the sea accounting only for the Antarctic land surface proper is at , and the farthest point when ice sheets are taken into account is . These points, calculated by the British Antarctic Survey, are quoted as being "the most accurate measure available" (as of 2005).

The southern pole of inaccessibility is far more remote and difficult to reach than the geographic South Pole. On 14 December 1958, the 3rd Soviet Antarctic Expedition for International Geophysical Year research work, led by Yevgeny Tolstikov, established the temporary Pole of Inaccessibility Station (Polyus Nedostupnosti) at . A second Russian team returned there in 1967. Today, a building still remains at this location, marked by a bust of Vladimir Lenin that faces towards Moscow, and protected as a historical site. Inside the building, there is a golden visitors' book for those who make it to the site to sign.

On 4 December 2006, Team N2i, consisting of Henry Cookson, Rupert Longsdon, Rory Sweet and Paul Landry, embarked on an expedition to be the first to reach the historic pole of inaccessibility location without direct mechanical assistance, using a combination of traditional man hauling and kite skiing. The team reached the old abandoned station on 20 January 2007, rediscovering the forgotten statue of Lenin left there by the Soviets some 48 years previously. The explorers were picked up from the spot by a plane from Vostok base to Progress Base and taken back to Cape Town on the Akademik Fyodorov, a Russian polar research vessel. The team found that only the bust on top of the building remained visible; the rest was buried under the snow.

On 11 December 2005, at 7:57 UTC, Ramón Larramendi, Juan Manuel Viu, and Ignacio Oficialdegui, members of the Spanish Transantarctic Expedition, reached for the first time in history the southern pole of inaccessibility at , updated that year by the British Antarctic Survey. The team continued their journey towards the second southern pole of inaccessibility, the one that accounts for the ice shelves as well as the continental land, and they were the first expedition to reach it, on 14 December 2005, at . Both achievements took place within an ambitious pioneer crossing of the eastern Antarctic Plateau that started at Novolazerevskaya Base and ended at Progress Base after more than 4,500 km (2,800 mi). This was the fastest polar journey ever achieved without mechanical aid, with an average rate of around 90 km (56 mi) per day and a maximum of 311 km (193 mi) per day, using kites as power source.

On 27 December 2011, Sebastian Copeland and partner Eric McNair-Landry also reached the southern pole of inaccessibility departing from Novolazerevskaya Base on their way to the South Pole to complete the first partial crossing of Antarctica through both poles, over 4,000 km.

As mentioned above, due to improvements in technology and the position of the continental edge of Antarctica being debated, the exact position of our best estimate of the pole of inaccessibility may alter. However, for the convenience of sport expeditions, a fixed point is preferred, and the Soviet station has been used for this role. This has been recognised by the Guinness Book of Records in regard to Team N2i's expedition in 2006–2007.

Oceanic pole of inaccessibility

Oceanic pole of inaccessibility at 48° 52′ 36″S 123° 23′ 36″W

The oceanic pole of inaccessibility () is the place in the ocean that is farthest from land. It lies in the South Pacific Ocean, 2,688 km (1,670 mi) from the nearest lands: Ducie Island (part of the Pitcairn Islands) in the north, Motu Nui (part of the Easter Islands) in the northeast, and Maher Island (near the larger Siple Island, off the coast of Marie Byrd Land, Antarctica) in the south. Chatham Island lies farther west, and Southern Chile in the east. This location is also referred to as "Point Nemo", a reference to Jules Verne's Captain Nemo. This Oceanic Point of Inaccessibility was famously used by H.P.Lovecraft as R'lyeh, the earthly home of Cthulhu.

Continental poles of inaccessibility

Eurasia

Distance to the sea in Asia, showing the two candidate locations for Eurasian Pole of Inaccessibility.

In Eurasia, the Continental Pole of Inaccessibility () is the place on land that is farthest from the ocean, and it lies in north-western China, near the Kazakhstan border. Earlier calculations suggested that it is 2,645 km (1,644 mi) from the nearest coastline, located approximately 320 km (200 mi) north of the city of Ürümqi, in the Xinjiang Autonomous Region of China, in the Dzoosotoyn Elisen Desert. The nearest settlements to this location are Hoxtolgay Town at , about 50 km (31 mi) to the northwest, Xazgat Township (Chinese: 夏孜盖乡; pinyin: Xiàzīgài xiāng) at about 20 km (12 mi) to the west, and Suluk at about 10 km (6.2 mi) to the east.

However, the previous pole location disregards the Gulf of Ob as part of the oceans, and a recent study proposes two other locations as the ones farther from any ocean (within the uncertainty of coastline definition): EPIA1 and EPIA2 , located respectively at 2,510±10 km (1560±6 mi) and 2,514±7 km (1,562±4 mi) from the oceans. These points lie in a close triangle about the Dzungarian Gate, a significant historical gateway to migration between the East and West.

Elsewhere in Xinjiang, the location in the southwestern suburbs of Ürümqi (Ürümqi County) was designated by local geography experts as the "center point of Asia" in 1992, and a monument to this effect was erected there in the 1990s. The site is a local tourist attraction.

Coincidentally, the continental and oceanic poles of inaccessibility have a similar radius; the Eurasian poles EPIA1 and EPIA2 are about 178 km (111 mi) closer to the ocean than the oceanic pole is to land.

North America

In North America, the continental pole of inaccessibility is in southwest South Dakota about 11 km (7 mi) north of the town of Allen (also considered the poorest place in the United States), located 1,650 km (1,030 mi) from the nearest coastline at . The Canadian pole of inaccessibility is allegedly in Jackfish River, Alberta , a few kilometres up the Peace River from where the Jackfish River (one of six Canadian rivers of that name, actually) flows into the former.

South America

In South America, the continental pole of inaccessibility is in Brazil at , near Arenápolis.

Australia

In Australia, the continental pole of inaccessibility is located either at or at , 920 km (570 mi) from the nearest coastline. The nearest town is Papunya, Northern Territory, about 30 km (19 mi) to the southwest of both locations.

Africa

In Africa, the pole of inaccessibility is at , 1,814 km (1,127 mi) from the coast, close to the tripoint of the Central African Republic, South Sudan, and the Democratic Republic of the Congo, as well as close to the town of Obo.

See also

• Pole of inaccessibility (Antarctic research station)
• Geographical pole
• Extreme points of Earth
• Land and water hemispheres
• Geographical centre

External links

• Team N2i reaches for POI and found Lenin!
• How to calculate PIAs