There are seven countries which have territorial claims on parts of Antarctica: Britain, France, Australia, New Zealand, and Norway, which all recognize each other’s claims; and Chile and Argentina, whose claims are disputed.
In practice, however, all claims are suspended under international treaty, and there are no checkpoints or immigration officers. For most people, a visit to Antarctica consists of a flight over it or a ride on a ship through its waters, neither involving disembarkation and thus both avoiding immigration formalities.
Land tourism does exist, and a permit is required. The vast majority of visitors will arrive by commercial ship or helicopter, and the tour operator is responsible for obtaining the necessary permits. You may, of course, need a visa for the country where your tour is departing from.
To land on the continent in a private vessel such as a yacht, you would need to obtain a permit yourself from your own government, if your country is a signatory to the Antarctic Treaty System. For example, Britons would apply to the Foreign and Commonwealth Office, Polar Regions Department; Americans would file the DS-4131 Advance Notification Form – Tourist and Other Non-Governmental Activities in the Antarctic Treaty Area with the Department of State’s Office of Ocean and Polar Affairs
Due to Antarctica’s extreme physical conditions and remoteness, only a few dozen yachts make the trip each year, and there are special yachting guidelines for Antarctic cruises.
For a list of tour operators, see the International Association of Antarctica Tour Operators.
From 101Visa:
No single government controls Antarctica, so visitors do not need visas to go there. But with the ratification of the Antarctic Treaty’s Protocol on Environmental Protection in 1998, all visitors who are citizens of countries that are signatories of the Antarctic Treaty must have a permit to visit Antarctica. Cruise ship passengers are covered under the permits applied for by the cruise company. Yacht passengers and crew, and anyone visiting Antarctica by air, should check with their national government to make sure they have their paperwork in order. If you are uncertain about your status, check with your tour operator.
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