A
compass rose is a star shaped icon which appears on a
map to indicate the
orientation of the map.
A full compass rose traditionally has 32 points with
north being the most prominent point.
North isn't always at the top of a map.
A polar map of the north pole has north at the center and a polar map of Antarctica has north pointing outwards in all directions.
Ancient maps were oriented as the creator of the map saw fit.
The Gough Map (approx. 1350) of England has north to the left whereas Erhard Etzlaub's Rom Weg (1501) showing the routes to Rome places Rome (and south) at the top of the map (both maps are described here).
There are even maps in which north's orientation on the map is different depending on which part of the map you're looking at.
For example, the British strip road maps produced by John Ogilby in 1675 depict a road between two locations.
Each road is drawn on the map as a relatively straight path with intervening towns and important landmarks depicted.
A compass rose indicating which direction is north appears every few miles along the route (the maps were drawn at a scale of one inch per mile).
Since the "real route" is often far from straight, the orientation of the various compass roses on a single map can vary considerably.
Sources
- the web page "MAP ROOM - Descriptions of the map images" located at http://www.bodley.ox.ac.uk/guides/maps/webmapsf.htm (last accessed 2002/10/06)
- the web page "Etzlaub RomWeg" located at
http://lazarus.elte.hu/~zoltorok/Cartartweb/cartart_etzlaub.htm (last accessed 2002/10/06)
- a 1675 Ogilby map showing the route from Abington to Monmouth
- the "True North" entry in a glossary(?) located at
http://naturalscience.lifetips.com/PPF/id/54796/Cat.asp (last accessed 2002/10/05)