Yes lines of latitude are always equal distances apart. The fact that they are equal distances apart can be proved from the fact that they never converge with one another. The lines are also called parallels and run from east to west. As it has been proved mathematically that parallel lines will always be equal distance away from each other, so lines of latitude are always equal distance from one another. Lines of latitude are actually used for the measurement of distance north and south of the equator.
