There's no line there, but if a cartographer chose to draw one on his
map or globe, then it would be the 'parallel' of 66° south latitude.
That would be the 66.5° S parallel.
The Equator
No, the Arctic Circle is located approximately 23 and a half degrees north of the North Pole, not south.
The Antarctic Circle, which is located at approximately 66.5 degrees south latitude, marks the southernmost point where the sun does not rise on the winter solstice. This line signifies the beginning of the Antarctic region's cold climate and is known for its extreme winter conditions.
The imaginary line located at 66.5 degrees south latitude is called the Antarctic Circle. This is the southernmost latitude at which the sun can remain continuously above or below the horizon for 24 hours during the summer and winter solstices, respectively. It marks the boundary of the Antarctic region.
The South Pole is at 90 degrees S latitude and is located on the continent of Antarctica. All of Antarctica is located within the Antarctic Circle which is at 66 degrees 32 minutes S latitude.
Those are the polar zones.
If you are south of about 66 degrees S, you are in the Antarctic region. If you are north of about 66 degrees N, you are in the Arctic region.
The Antarctic Circle is at 66 degrees 32 minutes S latitude. The Arctic Circle is at 66 degrees 32 minutes N latitude.
The Arctic circle is located at 66 degrees north.
The South Pole is at 90 degrees S latitude. The North Pole is at 90 degrees N latitude. All lines of longitude converge at both poles. The Antarctic Circle is at 66 degrees 32 minutes S latitude. The South Pole is located on the continent of Antarctica.
The island possession located at approximately 18 degrees N latitude and 66 degrees W longitude is Puerto Rico.