Important Lines on the Globe These lines are lines that we need to know and use the most in Geography.

Equator 0 degrees latitude that separates North and south Hemispheres.

Tropic of Cancer The Tropic of Cancer is the circle of latitude on the Earth that marks the most northerly position at which the Sun may appear directly overhead at its zenith. This event occurs once per year, at the time of the June solstice, when the Northern Hemisphere is tilted toward the Sun to its maximum extent.

Tropic of Capricorn The Tropic of Capricorn, or Southern tropic, marks the most southerly latitude on the Earth at which the Sun can be directly overhead. This event occurs at the December solstice, when the southern hemisphere is tilted towards the Sun to its maximum extent.

Arctic Circle One of the five major circles of latitude that mark maps of the Earth. In 2012, it is the parallel of latitude that runs 66° 33′ 44″ (or °) north of the Equator.

Antarctic Circle One of the five major circles (or parallels) of latitude that mark maps of the Earth. For 2012, it is the parallel of latitude that runs 66° 33′ 44″ (or °) south of the Equator.

Prime Meridian A prime meridian is a meridian, i.e. a line of longitude, at which longitude is defined to be 0°. A prime meridian and its opposite in a 360°-system, the 180th meridian (at 180° longitude), form a great circle.

International Date Line The International Date Line (IDL) is an imaginary line on the surface of the Earth, that runs from the north to the south pole and demarcates one calendar day from the next. It passes through the middle of the Pacific Ocean, roughly following the 180° longitude but it deviates to pass around some territories and island groups. The International Date line is on the opposite side of the Earth to the Prime Meridian. 180°