What most naturally follows?

How to read latitude and longitude on a map
Get familiar with the concept of latitude.
Latitude is a measure of distance north or south of the equator, which is an imaginary horizontal line around the exact mid-point of the earth between the 2 poles. The earth is divided up into 180 latitude lines on either side of the equator, called parallels.
These parallels run horizontally around the earth, parallel to the equator. 90 of them are north of the equator, while the other 90 are south of it.