The 180th meridian or antimeridian is the meridian which is 180° east or west of the Prime Meridian with which it forms a great circle. It is common to both east longitude and west longitude. It is used as the basis for the International Date Line because it for the most part passes through the open waters of the Pacific Ocean. However, the meridian passes through Russia and Fiji as well as Antarctica.
Country, territory or sea Notes Arctic Ocean Russia Wrangel Island Chukchi Sea Russia Chukotka Autonomous Okrug Bering Sea Amchitka Pass Passing just east of Semisopochnoi Island, Alaska, United States (at ) Pacific Ocean Passing just east of Nukulaelae atoll, Tuvalu (at )
Passing just west of the island of Cikobia, Fiji (at )
Fiji Islands of Vanua Levu, Rabi, and Taveuni Pacific Ocean Passing just east of the island of Moala, Fiji (at )
Passing just west of the island of Totoya, Fiji (at )
Passing just east of the island of Matuku, Fiji (at )
Southern Ocean Antarctica Ross Dependency, claimed by New Zealand
The meridian also passes between (but not particularly close to):
- the Gilbert Islands and the Phoenix Islands islands of Kiribati;
- between North Island and the Kermadec Islands of New Zealand;
- between the Bounty Islands and the Chatham Islands, also of New Zealand.