You currently live of the continent of Rane. Rane was only colonized 300 years ago and is a mixture of many of the civilized races. Most of the cities are located along the coast with the exception of Cirtius, the largest city on the continent resting atop Mount Rane, the one and only mountain on the continent.
Derdrew is a world like many others. People are born and die. In that time they meet each other. They learn to love or hate one another. They learn to build and destroy. They learn to wield magic and sword.
However Derdrew is also a world very different from many others. The sun rest in the sky perpetually at it's apex, never rising or setting. Time is measured not by the passing of the sun, but by the daily storms that come and bring a relief to the heat. The storms cause the mist to rise shrouding the land for half the day until they settle below the edges of the continents again. The coast of the continents abuts a sea of mist. To travel over the mist one must either ride a beast that can fly the hundreds or even thousands of miles between continents or fly in one of the great magical airships.
A world that has formed so differently than others has other difference as well. No true night means that your characters have never seen, nor even heard of stars. Nor is there a "north" in this world. Local navigation is based on moving to and from or around Mount Rane. Intercontinental navigation uses an Archolabe to measure the distance and direction of the warp and woof of the magical ley lines that run throughout the world.
Plant life is different. Your characters have never seen any type of grass. This include crop grasses like wheat, corn, barley, and bamboo. Instead of grass many different types of ferns and moss cover the ground. To supplement the vegetables grown in the fields large sections of forest are managed for the growing of mushrooms.
Animal life as well is effected. Animals with hooves are not natural to Derdrew. Your characters have never seen cows, goats, sheep nor horses. In additional magical creatures like unicorns and minotaurs are unknown. What they have seen are dinosaurs. Many different kinds. All over the continent.
One additional thing is that stone is quite rare. While metals like iron, tin, and copper are common, how they are obtained is a closely guarded secret by the dwarven elders. Because stone is so rare it is used mainly for religious purposes or as a great show of wealth.
Humans - Never one for staying in one place for long humans were the first to set about colonizing Rane.
Dwarves - Without the secrets to mining humans were forced call for dwarves to come and establish the mines to gather the metal and stone needed to build a nation.
Orks - While humans were first, the orks were only a decade behind them. Renowned across Derdrew for their impressive woodworking the Orks were welcomed with open arms by the humans.
Halflings - A civil war in their homeland forced a group of halfling to flee for better lands. They landed on Rane and are here to this day.
Gnomes - Once the richness of the metals from Rane became known, Gnomes arrived to work their own brand of magic.
Elves - The most recent arrivals, the Elves have been on Rane for little more that 50 years.
Goblins & Kobolds - No one know exactly when or how these races got to Rane. They weren't here 20 years ago and now they are.
The idea of Gaia, that the world is alive, is taken to the extreme in all of Derdrew's religions. All of the religions understand to one degree or another that the very ground is alive. Those of good or even neutral alignment understand that the ground should be protected. (Though they often disagree on exactly how that idea should be practiced.) Those of evil alignment will seek to steal that life force for their own use, or in some extreme cases destroy that life.
This is the core of the reason why dwarven mining is such a sacred secret that should be protected above all others. Once a dwarf is of age and if they are chosen by the Guild of Miners then they are taught the secrets of the mine for over 10 years before they are allowed to enter the mine. The dwarven elders understand that if those who would do the world harm learned what they know then they would have to power to take the life of Gaia for themselves. They point to Nargilazaril, the dead continent, as proof of their words.
More information from Discord:
Each "continent" is actually one giant tree that you guys live on top of.
None of you have actually seen the ground because it is miles below you
There is a layer of dirt, mulch, compost, etc that acts like dirt here.
However, if you dig too deep you start digging into the tree itself.
A little bit of this would be like a wood pecker digging out grubs
A lot of it and you kill the tree, and oops/
Remember that it is dwarves who gather stone and metals and gems that people use.
The mystery is how they get it without going down to the ground miles below