Maps of the Earth include many latitudes. They are the lines which divide the globe horizontally. Five of them have names. I have crossed four of them.
The parallels or circles of latitude bearing names
The latitude of the Equator is fixed. But the exact latitude of the others varies. The values below are for 6 January 2019 (Wikipedia).
- Arctic Circle (66°33’47.5″ N)
- Tropic of Cancer (23°26’12.5″ N)
- Equator (0° latitude)
- Tropic of Capricorn (23°26’12.5″ S)
- Antarctic Circle (66°33’47.5″ S)
The Arctic Circle
The Arctic Circle is the northernmost circle. It passes through Norway, where my picture was taken in 2017 from a ship crossing the line. This circle also runs through Sweden, Finland, Russia, USA, Canada, Greenland and Iceland. I have not been across it in any of these countries, save for flyovers. (Links are to Sandalsand’s articles.)
The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the sun can remain continuously above or below the horizon for 24 hours (at the June and December solstices respectively).
The Tropic of Cancer
This circle is sometimes called the Northern Tropic. It is the most northerly circle of latitude on Earth at which the Sun can be directly overhead (zenith). This takes place on the June solstice.
The Tropic of Cancer passes 16 countries: From Mauritania it continues east to Mali, Algeria, Niger, Libya and Egypt, all in northern Africa. Continuing in an eastward direction the line crosses Saudi Arabia, UAE (Abu Dhabi) and Oman. In Asia it crosses India, Bangladesh, Myanmar, China and Taiwan. In South America is cuts across Mexico and touches a couple of islands in the Bahamas.
I have crossed this line twice. The first time was in 1985 on a train from Guangzhou to Guilin in China. The second time I crossed it was a few weeks later, aboard a ship from Shanghai to Hong Kong.
The latitude of the Earth’s equator is by definition zero degrees of arc. The Equator is the only line of latitude which is a great circle. Its plane passes through the centre of the globe.
My picture from 1987 is from Ecuador, the only place I have actually crossed it on land or sea. The Equator passes through 11 countries: São Tomé and Príncipe, Gabon, Republic of Congo, Democratic Republic of Congo, Uganda, Kenya, Somalia, Indonesia, Ecuador, Colombia and Brazil.
The Tropic of Capricorn
This latitude is also called the Southern Tropic. It is the southernmost latitude where the Sun can be directly overhead. In the Southern Hemisphere it is the equivalent of the Tropic of Cancer in the Northern.
I crossed the Tropic of Capricorn in Namibia, and took this photo in 2018. I passed it in northern Chile in 1988 without paying attention at the time.
On land it passes through 10 countries: Namibia, Botswana, South Africa, Mozambique, Madagascar, Australia, Chile, Argentina, Paraguay and Brazil.
The Antarctic Circle
The Antarctic Circle touches outlying regions of the Antarctic land mass several places. This is a continent that I have never been to. I reckon that the crossing of the Antarctic Circle is utterly problematic on land.
There is only one notable longitude
The “vertical” lines from pole to pole, called meridians, are not differentiated by names. There is one exception. The Prime Meridian runs through the Royal Observatory at Greenwich, England. This is the zero degrees longitude. I visited this site many years ago (1976) and took this photo.
The Prime Meridian crosses eight countries: United Kingdom, France, Spain, Algeria, Mali, Burkina Faso, Togo, and Ghana. It ends on land in Antarctica, which is a continent and not a country.