Where can i start to look if i want to learn how to make geographically feasible fictional places. I'm trying to write an epic, yes, but i've been trying to write one ever since i read treasure island and lionboy (these two are my prime motivations for writing). I'll list the problems i'm facing currently (Please keep the technological context of 500-1000 AD in mind): 1. Rivers: I'm trying to send rivers everywhere so that people can farm everywhere and there can be a lot of cities and fertile land, but to make that possible im creating glaciers and mountain ranges everywhere too, how else are rivers formed? 2. Wetlands: I'm trying to create a complete kingdom under the protection of naturally created wetlands (the kingdom is embedded inside a huge wetland). Are wetlands difficult enough to maneuver that a whole kingdom can rest assured that nobody will cross it? What are the methods of converting wetlands into replenishing fertile lands? Can a patch of highlands(apprx the size of france/germany) embedded in the wetlands have fertile lands/rivers? If its a peninsula surrounded by only ocean and wetlands, would that change something? 3. Population: I doubt it comes under geography, but this is a issue too. I need to make enough arable land so that the population can shoot up, (i need to recolonise a catastrophically destroyed land/half-continent). My main concern is about the wetlands.