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.