<P> Arcs of circles of latitude are sometimes used as boundaries between countries or regions where distinctive natural borders are lacking (such as in deserts), or when an artificial border is drawn as a "line on a map", which was made in massive scale during the 1884 Berlin Conference, regarding huge parts of the African continent . North American nations and states have also mostly been created by straight lines, which are often parts of circles of latitudes . For instance, the northern border of Colorado is at 41 ° N while the southern border is at 37 ° N. Roughly half the length of border between the United States and Canada follows 49 ° N . </P> <P> There are five major circles of latitude, listed below from north to south . The position of the Equator is fixed (90 degrees from Earth's axis of rotation) but the latitudes of the other circles depend on the tilt of this axis relative to the plane of Earth's orbit, and so are not perfectly fixed . The values below are for 17 December 2017: </P> <Ul> <Li> Arctic Circle (66 ° 33 ′ 47.0" N) </Li> <Li> Tropic of Cancer (23 ° 26 ′ 13.0" N) </Li> <Li> Equator (0 ° latitude) </Li> <Li> Tropic of Capricorn (23 ° 26 ′ 13.0" S) </Li> <Li> Antarctic Circle (66 ° 33 ′ 47.0" S) </Li> </Ul> <Li> Arctic Circle (66 ° 33 ′ 47.0" N) </Li>

What are the 5 major circles of latitude