There are some points on Earth for which the following is true:

Starting from one of these points, you can walk 1 km South, then 1 km East, then 1 km North, and you will wind up back where you started from.

One such point is the North Pole. Where are others?

If a person were to walk towards the South pole from exactly 1km away from it he would end up at the south pole from there if he were to go to the east he would not be able to move because any movement means he would be going towards the north. Afterwards when he goes 1km noerth he will eventually end up at the place he began. Actually the number of points are infinite but lie in the locus 1km north from the the south pole