Getting the distance between two locations right

MaestroNaj

Greetings fellow Cartographers!

This must be simple but I'm not getting it...
I'm trying to figure out how the Info->Distance function works.
I've downloaded the World map from the ProFantasy Site. In case you don't have it I've attached it in this post.
I then proceeded to measure the distance between a few cities and looked-up their actual distances (in miles at http://www.indo.com) and then computed the ratio of these distances to see what I would get: here's the result

From to CC3 distance Acutal distance in Miles Ratio
==================================================================
Barcelona to London 1091 712 1.532303371
Barcelona to Rome 795 546 1.456043956
London to Paris 354 213 1.661971831
London to Rome 1389 897 1.548494983
Madrid to Istanbul 2375 1707 1.391329818

Needless to say I am confused. Either the location of these cities in the world map is wrong or the distance calculation on that web-site is wrong or both are wrong or I'm doing something wrong...

So my question is: What do I have to do to get the distance on this map to report back accurate distances in miles?

Thanks for your help!

Monsen

CC3 provides you the measurements in miles, but remember that a world map is a projection of a globe onto a flat surface. No matter how you do this, a flat map is NOT going to have the correct real-world distances between cities in all directions. This applies to all flat maps, not just maps in CC3, and is more pronounced the larger an area the map has to cover, and dependent on the projection chosen.

This poster also illustrates projections nicely