The map gap

As the world's oldest printed atlas sells for £2m, our impression of what the Earth looks like has changed almost beyond recognition. But even now, it's hard to find a truly accurate picture of our planet.

Looking down at a map, the viewer thinks their eyes are taking in a snapshot of the Earth. But are they?

Between the oldest and the most modern incarnation of the printed atlas there are 500 years of mapping history filled with debate over how to represent the world. How to show countries' size, relief and relations? How to project an almost-spherical surface on to a flat one, but keep it accurate?

"If you peel an orange, you can't lay it flat and there's never an answer to that," says Steve Chilton, chair of the Society of Cartographers.

And that is the problem: map-makers have always compromised for their art - tweaking scale, distance or area to paste the world down. Making Greenland loom large, or squashing Africa to a narrow frame in the process.