The study of geography in the realm of Dungeons and Dragons is less of a science and more of an art. There is simply more to it than just contour maps and river names: in addition to the vast deserts, mountains, swamps, and forests, the land is also woven in with magic, metaphysical aspects, and prophecy. Even after three long years of arduous and comprehensive travel across the world, the Children of Power only possessed the vaguest sense of where everything was and how the parts all interacted with each other. Many cartographers and anthropologists spend their lifetimes just trying to figure out a corner of the realm and all of its layers. Most never truly do.
Never mind the other levels of the realm: in order for this story to continue, one must be familiar only with the physical attributes of the realm of Dungeons and Dragons.
Sarinthis Geography
The mainland of the planet (Planet Aaldore) that the Children of Power had landed on was called 'Sarinthis'. It is akin to a continent on Earth: a large body of land surrounded by oceans and with different 'nations' or 'tribes' or 'governing bodies' within it. Escium was another continent that they had few encounters with. The other continents need no mention here. To be brief, they were just significantly less diverse and modernized than Sarinthis.
In Sarinthis, the geography was surprisingly simple. In the west, there were the great Isildras Mountains and rocky soil. The majority of manufacturing happened under the supervision of these towering giants. More heavily populated cities appeared here, centered about manufacturing plants. Mostly humanoids populated the area, but other species lived and worked here too (more integrated than in the east)… quite the variety of species, actually, save for the elves. Elves stayed far away from the west and its large cities and grimy inclusion. Areas like the Maze of Darkness could be found in the majestic folds of Sarinthis' main mountain range.
To the east lay rolling hills and fertile land perfect for farming. Smaller towns formed around large plots of property, and many families remained put to help with harvest. Being the breadbasket of the continent was no easy feat… the labor was hard and toiling. People segregated more in the east: the only people you could trust were those in your family. While the cities of the west had high crime rates, here in the fields, nobody was present to protect you. 'Friendship' did not seem to truly exist. Towns were wary of newcomers, and families ushered their children in at night.
Turad, the City of Light, was in the east. The skies were clear there: perfect for star gazing. Tardos was also east. Krelm Valley, the Hills of Never (near the Citadel of Shadows: the only really ominous fortress there… the sun cannot penetrate everywhere): all took residence amongst the gentle slopes and farmland.
The north held forests, while the south held marshes (intermingled with either mountains or grasslands, depending how east or west these forests or marshes were). The treacherous marshes held sturdy towns that the Children of Power visited often (most of their adventures were southwest): Mindrel, Shalderon, and Cloud Bear territory all were present in the thick, swampy lagoons. The infamous Swamp of Shadows took up most of the area, with the Grottel of Darkness inside it as well as some of Venger's prison-camps.
Venger's castle was southwest… hidden by mountains and surrounded by swamps. His palace was near Varla's small village. The southwest was a nightmare of a place to live in, and the people were known for their stubbornness and resolve. You had to have those attributes to merely wake up each morning: disease spread through the marshes like wildfire. Bandits and monsters ran rampant, devouring people and burning villages in their wake.
A major river, the Alicorn, cut the continent in half, flowing from west (elevated land) to the east (it suddenly went south after going 3/4ths the way of the continent… an odd position that geographically made no sense… the shape of the Alicorn was the thesis topic for many scholarly articles). Sending goods from east to west against the current was extremely expensive. Not to mention that, in the heart of Sarinthis, there lay the Dustlands, which made trade nearly impossible for non-professionals.
The Dustlands: miles and miles of nothing but terrible desert situated in the exact heart of the continent. Many theories exist as to why it was there, where the best soil logically should be. Scholars cite ancient warfare that burned fields and depleted the nutrients in the soil. Zealots believe that a fairy queen cast a spell that created the wasteland in order to separate the industries from the farms, to keep the people from collaborating and becoming stronger than she. Romanticists quote that a king (with magical abilities) swore away all forms of water in the central area of the country to keep himself from crying after the brutal demise of his family.
Whatever the reason, the Dustlands were there. In the center of the country there were no cities. No towns. No empires. Nomads, tribes, and gang organizations ran the center, and facilitated the trade between east and west. They were constantly warring and grappling for power: politically, it was a nightmare. No one could, at any time, state who was top dog.
Ramoud's kingdom was in the east, but, like many prosperous kings, he had the resources available to him to travel through the Dustlands. He typically avoided the Dustlands and was wary of the troubles there, but he had to enter them to find Aiyesha (which was where he met the Children of Power).
In summation: Sarinithis is the focus. North: forests. South: marshes. East: farmland. West: mountains (Isildras)/industry. Center: Dustlands. Major river: the Alicorn.
On Monsters
To maintain manageable monster levels, Helvietus (a minor planet just within a suitable magic-trafficking distance) was set up as the prison planet. En masse, each year, all prisoners and monsters are sent there. Helvietus itself is protected from the magic and sorcery the monsters are capable of, so there can be no magical exodus from the prison planet.
Until the main prisoner transport occurs on the winter solstice, many temporary prisons have been set up on Aaladore. In Escium (which is nomadic deserts for the most part: they're the biggest trade partner with plentiful Sarinthis for this reason [they have precious natural resources: the realm's equivalent to our oil]) there are many of these prisons. You can't really hurt civilians in empty deserts, now can you? Sailors that ship prisoners from the Sarinthis mainland to Escium are paid dearly, but it's a dangerous job.
In Sarinthis, the main prison keep lies in the mountains to the west. The mountains make it hard for prisoners to escape, but expensive to run. The need for resources to keep the prison running led to the creation of Etreos a few miles away: the largest city in Sarinthis now. It is the capitol of one of the largest empires on the continent, Liir (3x the size of Ramoud's), which is run by noble King Phillip.
Sure, it was a nice place. Beautiful sunrises over the mountains. Starry, clear skies at night. Not too warm during the midday (like in the scorching east) because of the shade of the mountains. Great place to start a family, they say. More people began to do so as time went on, migrating to the empires Liir, Azur, and Ramadaron in that region. There was good business there… good money to be made. And hey: when Venger turned after the era of the Children of Power, why not settle in the west? His palace, once freakishly close to Etreos now was a beacon of light. Venger had turned into a sort of super-police power that would help rather than hurt, and populations in the west grew seemingly overnight.
It's a nice place. Good food. Friendly company… or as good as you could find in the realm. And the entrance to Etreos Prison was out of sight due to a large mountain. Put out the thought of 200,000 bloodthirsty killers behind those iron doors. Don't mind that. Just remember not to haggle too much with the baker, or you won't get service anymore.