User blog comment:Zippertrain85/The reasons why Serana is not from the First Era./@comment-9156240-20130508234036/@comment-9062114-20130509204432

Why is that relevant?

I'm not quite sure. If they are from the First Era it would've had to exist at that time, since Serana knew where it was when you let her out, but for the reasons I'll explain it couldn't have existed that long ago.

They were Nords from the early First Era, their was virtually no place they could go, it's like today where everyone knows each other because of the Empire, back then, they might have not even known there was more world outside of Skyrim.

No stlye like that existed back then. The Roman/European castle look didn't exist back then. It started coming up when the Bretons became a race. Also, materials like Marble are not common and Skyrim (and therefor not used) so how would they get enough to do a whole castle. So many loose ends.