Better way to desing a large terrain...

#1 Photoshop, Terragen, Paint Shop Pro, Gimp, etc... Anything that can do large heightfields.

#2 @Juan

What kind of a terrain are you trying to make. I would be very happy to help you learn to make the kind of terrain you want. Let me know what you need and I'll help.

#3 Real areas? maby you should try to use a physical map of the area, or a google earth map or something like that to make the hightmap?

good luck,
Lee-Orr