Lots of affects to consider and not all of them are documented in any map.


Wind, climate, rainfall, seismic activity, pollution all impact land in ways not shown on most fantasy maps - and we haven't even touched on Magic. With many elements not explained you have a larger capacity to make things the way you want and call it 'realistic' - some unseen force makes it so.


You can make broad gestures - river flow always going down is a good one.

Old areas typically have more erosion.
Mountains next to trenches or canyons will probably be steep and young.
Evergreens in the north, palms in the south.
Seas are salty and deep. Rivers and lakes not so much.
Islands form in chains like the top of a ridge.
Coasts have a wild and random curve to them. They're best generated rather than drawn IMHO.

Personally, I find a great deal of 'realism' is a sense best satisfied by a random element. I question my decisions if I draw a coastline but I feel much more confident with a generated one that I 'discover'. I think its just an unnatural act to make land.


Sigurd