Antarctica...
The Antarctic Circle runs through the Southern Ocean, which surrounds Antarctica.
None.
No point in the USA is less than about 5,900 miles from the Antarctic Circle.
There are no countries on Antarctica.
None. The only landmass it passes through is Antarctica, which contains no countries, mainly just science stations run by countries like Britain, Chile, Australia and Argentina. If you are also including the Arctic Circle in this question, the Arctic Circle passes through: Russia, Finland, Sweden, Norway, Iceland (the island of Grimsey), Greenland (which is still sort of technically part of Denmark), Canada, and the United States. So it passes through eight countries.
South America, Africa and Asia
The equator runs through:AfricaSouth America
Russia
Three: Europe, Africa,and Antarctica.
The equator runs through South America and Africa.
North America, Antarctica
The prime meridian runs through three continents. These continents include Europe, Antarctica, and Africa. The prime meridian is also referred to as the Greenwich meridian.