It was just that, such a 'small' and old stronghold could still be used as a shelter against natural disaster or monster and beast tide.
The stronghold was located at the top of the snowy mountain area, and the materials used to build the stronghold were naturally immune to extreme cold and similar disasters.
The terrain was good because it was high up the mountain with a river full of edible fish around.
There was also a small fruit forest where the inhabitants were mostly docile herbivores.
This place was the most suitable place to be chosen as a temporary base because coincidentally, there were some old arrays and barriers that could still be activated there.
The snowy mountain did have several dimensional holes, but the distance was far away from the top of the mountain where the base existed.
Not to mention that abyss demons were naturally immune against hot temperature but they were a bit weak against cold.
