'Strongholds' in the Bible

He devastated their strongholdsand destroyed their cities.The land and everything in it shudderedat the sound of his roaring.

“Tell them this: This is what the Lord God says: As surely as I live, those who are in the ruins will fall by the sword, those in the open field I have given to wild animals to be devoured, and those in the strongholds and caves will die by plague.