So I have been working on a world where space has been "cracked" by some mysterious disaster which plunged the world into chaos.
It is not immediately apparent - i.e. no giant glowing holes in the sky, but the world map no longer follows the rules of geometry;
- The journey between two settlements may be longer one way than the other
- Retracing your steps may not return you to your destination
- A "pocket" that can only be reached by one specific route. i.e - travellers from the wrong direction will bypass altogether
- Places that occupy the same location on the map, but are completely separate
The changes are large enough that they wouldn't necessarily affect travel within a settlement, but would only become a factor over a couple of days of travel.
The survivors are located in a series of villages and settlements scattered across the continent where the story takes place. Communications and trade routes are being reestablished. This is some time after the apocalypse- possibly a generation or two, so the immediate aftermath has been dealt with. There are no GPS or communications satellites, though some maps of the world world remain.
My question is - how hard would it be to discover the distortions using traditional cartography? Could you definitively prove that space has been warped, taking into account survey errors, etc etc?
EDIT: Typo and clarifications