mount everest, Chile, Tibet, Bhutan, maybe Switzerland, etc are protected by mountains,sorry i did not do all of it, i was confused.
The opinions and prejudice of an author in writing.
I believe that those two elements greatly affect bias in history because we can never be 100% sure of everything that (may have) happened in history (especially farther in the past), so opinion can affect a historian's writings. Also, everyone is prone to some sort of prejudice, so this can also affect history.
The Red Sea, the Arabian Sea, and the Persian Gulf