How do I know the size of my world, and its population

[Falconius]

I think Gumboot is right, horses are not significantly faster than people. I do however think they can be pushed harder than people and that when they are they also move faster. This will however result in injuries or loss of the horses, they also present an absolute logistical nightmare if you can not depend of a supply of feed on your route. They are a logistical nightmare in general even if you do have a sure supply of feed on the route, anything other than really small parties likely have spare mounts and packhorses/mules to help.

There is good reason donkeys and mules were so heavily used in the past and are used even today, and it has nothing to do with their sunny disposition. Same thing with camels. Horses are good for many things but long distance travel is not the area in which they shine.

Edit: Oh right as to the OP http://www.cartographersguild.com/tu...e-realism.html is a pretty interesting tutorial on just what you want to know.