User blog comment:Zippertrain85/The reasons why Serana is not from the First Era./@comment-26474238-20130514055034/@comment-26474238-20130514064426

The ancient Nordic designs seen in the tombs were exclusive to those following the dragons and dragon priests, which has the knowledge of the timeless and immortal dragons to help them technological wise. Nothing states that Castle Volkihar was made by the ancient Nords, and then there's the assumption of the the ancient Nordic people under the dragons being the one that made the castle.