The mountain range where the Evil Spirit Valley was located was very wide.
This was because it was on the east side of the Catacombs world. This mountain range went north and south. It was basically the end of the east, isolating this Catacombs world. Very few people could pass through this mountain range to the back.
According to their estimation, this mountain range stretches for tens of thousands of miles from north to south. The most dangerous area was the circular area that was thousands of miles long in front of him. This was the especially dangerous place they had summarized. It was easiest to see the Evil Spirit Valley.
The reason why the Evil Spirit Valley was so famous was because the person who escaped said that there were dead undead everywhere in the valley. These undead kept wailing and hissing, tearing off every inch of flesh and blood of those who entered.