Pole of inaccessibility

In geography, a pole of inaccessibility is a special place that is the farthest or most difficult to reach in a certain area, like a piece of land or water. This idea helps us find the spot that is the hardest to get to from a border, such as the edge of a continent or an island.

Often, this means finding the place that is the farthest from the coastline. For example, in a big landmass like a country or continent, the pole of inaccessibility would be the spot deep inside where you would have to travel the longest distance to reach the ocean. The same idea can be used for a body of water, finding the point farthest from the shore.

To imagine this, picture drawing the biggest possible circle inside an area, where the circle only touches the coastline but never goes beyond it. The center of that circle is the pole of inaccessibility. If the coast is not very clear, finding this point can be a bit tricky too.

Northern pole of inaccessibility

The northern pole of inaccessibility, also called the Arctic pole, is a spot on the Arctic Ocean pack ice that is farthest from any land. It is hard to reach because it is far from shore.

Explorer Jim McNeill worked with scientists to find the exact location in 2005. The new spot is about 1,008 kilometres from the nearest land. Because the ice moves, nothing can stay there forever. In 2024, a French ship called the Le Commandant Charcot became the first ship to reach this far-away spot.

Southern pole of inaccessibility

The southern pole of inaccessibility is the spot on the Antarctic continent that is farthest from the Southern Ocean. Different groups have suggested slightly different locations for this point because deciding where the true edge of the land begins can be tricky. Some say the edge is where the ice meets the water, while others look at where the ice is firmly attached to the land.

This faraway spot is much harder to reach than the geographic South Pole. In 1958, a team from the Soviet Union built a temporary research station there. Since then, many explorers have traveled to this remote place. Some have used kites to help them move across the snow, while others have walked or skied without any machines. Even with modern tools, the exact spot can change a little because scientists are still learning exactly where Antarctica’s edges are.

Oceanic pole of inaccessibility

The oceanic pole of inaccessibility, also called Point Nemo, is located at roughly 48°52.6′S 123°23.6′W / 48.8767°S 123.3933°W / -48.8767; -123.3933. It is the spot in the ocean farthest from any land. If someone fell overboard from a ship here, they would be as far from land as possible. It is in the South Pacific Ocean, equally distant from three nearby lands: Pandora Islet of the Ducie Island atoll (part of the Pitcairn Islands), Motu Nui next to Easter Island, and Maher Island near Siple Island close to Marie Byrd Land, Antarctica. Each of these places is about 2,688 km (1,670 mi) away.

Because this area is very far from any regular ship or airplane routes, sometimes the closest people are astronauts on the International Space Station when it passes overhead. The area around Point Nemo is also called a "spacecraft cemetery" because many old satellites and space stations are brought down here when they can no longer be used. The International Space Station is planned to fall here in 2031.

Continental poles of inaccessibility

Eurasia

The Eurasian pole of inaccessibility is in northwestern China, near the Kazakhstan border. It is the farthest point on land from the ocean.

Earlier calculations placed it about 2,645 km from the nearest coast, in the Xinjiang Autonomous Region of China, in the Gurbantünggüt Desert.

Africa

In Africa, the pole of inaccessibility is near the town of Obo in the Central African Republic, about 1,814 km from the coast.

North America

In North America, the continental pole of inaccessibility is on the Pine Ridge Reservation in southwest South Dakota, about 1,650 km from the nearest coast.

South America

In South America, the continental pole of inaccessibility is in Brazil near Arenápolis, Mato Grosso, about 1,504 km from the nearest coast.

Australia

In Australia, the continental pole of inaccessibility is about 920 km from the nearest coast, west-northwest of Alice Springs.

Methods of calculation

To find a pole of inaccessibility, scientists use computer models and tools. They start with maps of coastlines, like the GSHHG and OpenStreetMap. These maps show where the land ends and the water begins.

Next, they need a way to measure distances. Some methods flatten the Earth, while others use its round shape. New methods help get even more accurate results.

Finally, they use special math to find the point farthest from the coast. One way is to start with a grid of points, find the farthest from the coast, and then zoom in closer. Another method uses 3D shapes to pick starting points and refines them. These different ways can give slightly different answers, but they usually agree closely.

List of poles of inaccessibility

Poles of inaccessibility are special places that are very hard to reach. They are often the farthest points from the coast on land or water. Some people have tried to find these points, and a table below shows some of their ideas. But this list is not complete, and there may be more work done on this topic in the future.