Deep Exploration

So as they had cleared up the mess that was covering the ladder, they went ahead and descended downwards where there was a mysterious doorway. Simon then made use of his selfie stick to check whether this was a safe place to enter for the both of them or not. There were two rooms. Space under was quite big. They did not expect this at all but could see that there was ample space for people to sleep in and hide. But who were they hiding from exactly?