Lines of longitude are also known as meridians. Lines of longitude and latitude create a grid pattern on the globe for navigation. The Earth is split into 360 lines of longitude.

The first number is always the latitude and the second is the longitude. It easy to remember which is which if you think of the two coordinates in alphabetical terms: latitude comes before longitude in the dictionary. For example, the Empire State Building lies at 40.748440°, -73.984559°.

The Equator is the line of 0 degrees latitude. Each parallel measures one degree north or south of the Equator, with 90 degrees north of the Equator and 90 degrees south of the Equator. The latitude of the North Pole is 90 degrees N, and the latitude of the South Pole is 90 degrees S.

Important lines of latitude:

• the equator (0°)
• the Tropic of Cancer (23.5° north)
• the Tropic of Capricorn (23.5° south)
• the Arctic circle (66.5° north)
• the Antarctic circle (66.5° south)
• the North Pole (90° north)
• the South Pole (90° south)

The prime meridian is the line of 0° longitude, the starting point for measuring distance both east and west around the Earth. The prime meridian is arbitrary, meaning it could be chosen to be anywhere.

The meridian that runs through Greenwich, England, is internationally accepted as the line of 0 degrees longitude, or prime meridian. The antimeridian is halfway around the world, at 180 degrees. It is the basis for the International Date Line.

Any circle drawn around the Earth divides it into two equal halves called hemispheres. There are generally considered to be four hemispheres: Northern, Southern, Eastern, and Western. The Equator, or line of 0 degrees latitude, divides the Earth into the Northern and Southern hemispheres.

Largest cities straddling the Prime (Greenwich) Meridian

• London, United Kingdom: 8,538,689 (2014)
• Accra, Ghana: 2,291,352 (2013)
• Bordeaux, France: 851,071 (2011)
• Valencia, Spain: 809,267 (2010)
• Zaragoza, Spain: 666,058 (2014)
• Tamale, Ghana: 562,919 (2013)
• Brighton, United Kingdom: 273,400 (2011)

Miami is at the same latitude as Saudi Arabia. Honolulu at the same latitude as the Sahara desert. Los Angeles, San Diego, Phoenix and Houston are all at the same latitude as North Africa. Anchorage is further south than Reykjavik.

London

Quito

Quito Is The Closest Capital City To The Equator, South America Stock Photo, Picture And Royalty Free Image.

The countries through which the equator runs are:

• São Tomé and Principe.
• Gabon.
• Republic of the Congo.
• The Democratic Republic of the Congo.
• Uganda.
• Kenya.
• Somalia.
• Maldives.