I mean, we are suppose to be "in middle of nowhere" ... why would anyone build "proper necropolis" or "whole network of catacombs" in such place?
Well, aside for the fact that in the Forgotten Realms if the campaign requires it there can be conveniently-placed necropolis and rests of ancient civilizations even behind your bathroom... I don't think anyone here was advocating for having massive and complex dungeons here and now?
Or did you miss that we are supposed to spend the almost entirety of the second act in Baldur's Gate and surrounding areas?
Not to mention that incidentally we already have a Temple of Selune, burying a section of Underdark hosting a massive ancient forge, on the doorstep of a gigantic temple of Shar, so I'm not sure how the "middle of nowhere" excuse is going to fly.
