Null Island is a non-existant land mass where the Zero Degrees latitude and Zero Degrees longitude intersect. There is a permanent buoy located there, but the location is in the eastern Atlantic Ocean in the Gulf of Guinea, off the coast of Africa.

Zero degrees longitude is the east/west designation of any point on Earth. This line is called the Prime Meridian and is a north/south semi-circle from the geographical north pole to the geographical south pole. It was chosen to be located in Greenwich, England. West longitudes go 180 degrees west of there through the Atlantic Ocean and to the Americas. East longitudes go east from Greenwich through Europe, Africa and Asia. At 180 degrees either east or west from the Prime Meridian is another imaginary line, called the International Date Line.

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