Basic info
Demistable routes
The demistable routes are stabilized only by their use and maintenance. Abandoned or neglected routes are subject to the twisting and reshaping effects of the Viaduct. Some shard inhabitants are able to use specific techniques or construction to establish and stabilize such routes, but even the most elaborate and well-designed require constant upkeep to varying degrees or be lost to time.
The reshaping effect largely happens where there is nobody to observe it. In essence, once lost in the Viaduct one can easily turn around and become lost; the path you just traveled may shift when you are not observing it. There are some techniques for traveling through recursively-changing places, but even these are far from reliable.
In a broader sense the landscape may change in between two established locations such as trading posts. The path may be demistable with use of the resistant materials as guideposts, paved paths, etc. and occasional patrols along the pathways help reinforce the observer effect, however the path between the established locations will typically snake different route between different geographic features each time traveled.
Basically a thread of connection can be established and managed between two points, but that thread will be wound around different things at all times. While an exact route cannot be locked down, the motifs and themes will be constant. So, guides and scouts can specialize in the variety of hazards and threats common to that location, but must always be on their toes since one path can never be tread twice.