----------------------------Original message---------------------------- Dear list (and Nick!) Map projections not based on the poles of rotation of the earth are quite common, though not necessarily straightforward. In principle, ANY map projection can be constructed on any arbitrary pole - the mathematical dodge is to transform the geographic coordinates to a new pole (fairly simple spherical trigonometry) and then apply the usual projection routines. An example that is available on the Web is the Logo of the Scott Polar Research Institute (http://www.spri.cam.ac.uk/), which is an oblique aspect of the Mollweide Projection. A lot of useful information can be found in the documentation for Proj, a free projection conversion utility that can be downloaded from kai.er.usgs.gov/pub/PROJ.4. It has extensive documentation in Postscript format. The main reason that most projections stick to "natural" projection directions is that the mathematics for dealing with a non-spherical earth become very nasty! Spherical versions of projections are not affected, and for world maps or small scale maps these are quite appropriate. It is worth mentioning that map projections are mathematical entities which have an existence regardless of whether anyone has used it for publishing a map. Most so-called "new" projections are minor variations on well known projections. The (IMHO) dreadful Peter's projection is an example of this - it is simply a particularly awful version of the Lambert Cylindrical Equal Area projection, known since the 18th century! A Paul R Cooper GIS Manager British Antarctic Survey