Planebreak - End of an age
A Dwarven factory city, Bastion lies in a long valley that dead ends into a cul-de-sac. The entire valley is nothing but factories, foundries, rail stations, warehouses and other such structures with living quarters thrown in as an afterthought. If it can be built, you can likely find it in Bastion.
The city actually gets it’s name from what is simply known as The Gate. At the end where the valley cul-de-sacs, the entire cliff face has been turned into a massive stone and steel gate leading down at a 45-degree angle. The huge tunnel beyond the gate leads down to Markibyr, the City of Shadows, a Drow city. Over the years, the Dwarves had built a rail system to allow for easier travel between the Drow city and the surface.