The Prime Meridian is located at a longitude of 0 degrees. It serves as the reference line for the world's longitudinal coordinate system, dividing the Earth into the Eastern and Western Hemispheres. The Prime Meridian runs through Greenwich, London, where the Royal Observatory is situated. This line is crucial for navigation and mapping, establishing a baseline for time zones and global positioning systems. The significance of the Prime Meridian in geography cannot be overstated, as it plays a vital role in global communications, travel, and international timekeeping.