Viewport Artifacts when working with big scales Has anyone encountered those lines which look like z-fighting already? 
They only occur when the scale that is being worked on is relatively big.
When switching to orthographic this problem does not occur.



My island is 320x320m in size with metric as Unit and 1 as Unit Scale. 
Any ideas how to fix this?
Changing the clipping to:
Start: 1m and End: 1km
as suggested by @user1853 worked!