As a globe, our planet can be divided into four hemispheres: Northern, Southern, Eastern, and Western. The Northern and Southern Hemispheres are divided by the Equator at 0 degrees latitude. The Eastern Hemisphere covers everything east of the prime meridian (0 degrees longitude, which historically passes through London’s Royal Observatory, Greenwich) and west of the 180th meridian (180 degrees longitude, also known as the antimeridian), which mainly passes through the Pacific Ocean. The Western Hemisphere is everything west of the prime meridian and east of the 180th meridian.
If you want to visit all four hemispheres within the confines of one country, you'd have to head to the remote Pacific island nation of Kiribati, as both the Equator separating the Northern and Southern Hemispheres and the 180th meridian separating the Western and Eastern Hemispheres pass through water (though not land) belonging to Kiribati. Consisting of 33 low-lying islands, Kiribati is spread across 1.33 million square miles (3.44 million sq km) of ocean. However, the country’s landmass is only roughly 313 square miles (811 sq km).
When you consider countries with overseas territories, however, the question of which countries have land in all four hemispheres becomes more nuanced. The United Kingdom, France, and the United States all have their main landmasses in the Northern, Western, and Eastern Hemispheres, but when including overseas territories, each of those nations has land in the Southern Hemisphere, as well.
One world, four hemispheres:
- French overseas regions and collectivities in the Southern Hemisphere include La Réunion, Mayotte, New Caledonia, French Polynesia, and Wallis and Futuna. The British Overseas Territories of St. Helena, Ascension and Tristan da Cunha; the Falkland Islands; and the Pitcairn Islands are all located in the Southern Hemisphere.
- All 50 U.S. states are located in the Northern and Western Hemispheres, although a small portion of Alaska also extends into the Eastern Hemisphere. However, if you were to visit the territory of American Samoa, you’d be in the Southern Hemisphere.
- Kiribati’s 33 islands are divided into three island groups: the Gilbert, Phoenix, and Line islands, plus Banaba, a raised coral island. The Gilbert Islands are the main archipelago, with more than half of the country’s roughly 119,000 inhabitants living on Tarawa atoll, mainly in the capital, South Tarawa.
- Kiribati has been a sovereign state since 1979, when it gained independence from the United Kingdom. While English is an official language in Kiribati, it is not widely spoken outside of Tarawa. Nearly everyone speaks Gilbertese, an Oceanic language.
- On the other side of the planet from Kiribati, the point at 0°N 0°E where the Equator and the prime meridian cross is located in the Atlantic Ocean. Although there is no land there, it has become known as Null Island, and is marked by a permanent buoy. Null Island is located in the Gulf of Guinea, around 370 miles (600 km) off the coast of West Africa; the closest country is Ghana. As a continent, Africa has land in all four hemispheres.
- The Southern Hemisphere is home to 38% of the Earth’s landmass and just 10% of the world’s population.
