Given a text passage, come up with an appropriate title for it. The title should accurately represent what the main focus of the passage is. The title of a passage may be present in the first few sentences of the passage and/or be referred to multiple times in the passage. The title should be 1-5 words long.
Q: The 180th meridian or antimeridian is the meridian 180 east or west of the Prime Meridian , with which it forms a great circle dividing the earth into the Western and Eastern Hemispheres . It is common to both east longitude and west longitude . It is used as the basis for the International Date Line because it mostly passes through the open waters of the Pacific Ocean . However , the meridian passes through Russia and Fiji as well as Antarctica .
A:
180th meridian