Which line is located at 0 degrees longitude?

The Prime Meridian is the line that is defined as 0 degrees longitude. It serves as the starting point for measuring longitude, which is the angular distance of a place east or west of the Prime Meridian. This line runs through Greenwich, London, and is crucial for navigation and timekeeping across the globe. By establishing a standard reference, the Prime Meridian helps in determining time zones and is integral in global positioning systems (GPS).

In contrast, the Equator is situated at 0 degrees latitude, dividing the Earth into the Northern and Southern Hemispheres, while the International Date Line is approximately at 180 degrees longitude and is used to determine calendar days across the globe. The Tropic of Cancer is located at approximately 23.5 degrees north latitude and marks the northernmost point where the sun can be directly overhead. Each of these lines serves a different purpose, but only the Prime Meridian is associated with 0 degrees longitude.