This imaginary circle goes around the middle of the earth for 24,902 miles. It divides the Northern Hemisphere from the Southern Hemisphere and is exactly half way between the North and South Poles. An imaginary line where the date changes one day when passed. It is one day earlier east of the line than it is on the west. Meridians Imaginary lines that run north and south on a map from pole to pole.
Meridians express degrees of longitude , or how far a place is away from the prime meridian.
The prime meridian runs through Greenwich, England. Longitude is used together with latitude to form a grid on which it is possible to locate any place on the earth. Parallels Imaginary lines that run east and west on a map. Parallels represent degrees of latitude , or how far a place is away from the equator. One degree of latitude equals about 69 miles.