Antarctica 

Antarctica is a continent which is not owned by any country. Antarctica treaty was signed which allowed seven countries to make territorial claim in some parts of Antarctica however the territorial claim do overlap with each other. For instance one country might have a research facility in other country's territorial claim. Originally there were seven countries that signed the treaty. Today there are 12 countries that govern Antarctica. And then there are countries which are not part of the treaty or cannot make territorial claim but they have research facilities in claimed territories as well as other part of Antarctica such as Italy, Russia, Pakistan, Ukraine, India and United States.

Antarctica is world's 5th largest continent by its area but it is the driest and coldest place on Earth. There are many features about Antarctica which make it so unique. First of all it is covered by thick ice sheet which is one of the reasons why it is an important continent because underneath all that ice is most of world's fresh water locked up. What also makes it unique is that is does not has any native human population. However there are at least 11 people which are reported to born in Antarctica. The first person who was documented to born in Antarctica was born to Argentine parents therefore he was given Argentine citizenship. Although he was born in Argentina's territorial claim in Antarctica but the territorial claim is not internationally recognized as territorial claim overlaps with British and Chili's claim. Since Antarctica is not owned by any country therefore there is no border and you do not need permission to travel to Antarctica. However if you travel to parts of Antarctica where a country can make a territorial claim under the treaty, you will need permission from that country to visit that part of the continent. 

Scientific research in Antarctica is done on variety of research areas including but not limited to environment, biology, geology, earth science and oceanography. The research on climate and weather also helped to understand the global problems such as climate change which is also the biggest threat to Antarctica and rest of the world. Due to the climate change if all the ice in the Antarctica melts the sea level around the world will rise and cover the coastal cities (cities which are located between the transition areas of land and sea). Most of the land area will also be shrink.

While due to its cold and dry weather the continent may not be suitable for human population but it is home to many species ranging from mammals to birds to marine species to invertebrates (animals which do not have backbone). There are at least 235 species living in Antarctica. These species are classified as extremophiles (animals that live in extreme weather conditions).