When entering the Hakkvild's High Hall from Craglorn, you will notice the shape of door at the outside is different from inside (outside door shape looks like a Great Nord Temple door, inside door shape looks like from Hall of dead). When you move to the hall house through the tomb, you will find the door shape is also different, and I currently cannot find another player home with such "obvious mistake"
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Additionally, when you are inside the house and open the world map, it shows on the figure below, and your Hakkvild's High Hall is only at the Southwest corner of the map! This is not natual, and you can also notice the "player house"icon on the map, however you have already inside the house right? Normally, only when you are outside your house, you need the icon for quick trasportation. And you can see there is a larger town on the map, which is the city Falkreath.This may indicate the map was originally not designed for this house, maybe this is the map for a open city Falkreath!
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However, you cannot travel to Falkreath, because there is a locked door in your own house! I never see any player house has a door lock!
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You can compare the Falkreath dungeon map and the Falkreath city map, and the map on the left looks so similar to a regular open city map! Your house is just above the hall of the dead! That's why before you enter your hall, you need to walk through a tomb, that't the Falkreath city hall of the dead! You cannot enter the "ghost section" due to a locked fence inside the tomb.
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From what has been discussed above, the Dungeon Falkreath might be originally designed as a open city such as Alinor or Rimmen, however this design was eventually canceled, and the whole city was redesigned into a dungeon. This could explain why there are some locked doors, maybe these door were originally used for player to leave their home and enter Falkreath.
The unmatched door shape mentioned at the beginning may indicate the originally design needs player enter Falkreath first, however Falkreath now is a dungeon, so player have to enter Hakkvild's High Hall from Craglorn, rather than through Falkreath hall of the dead in Riften
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So, guess the designer of Hakkvild's High Hall may be trying to tell player Falkreath was "once" designed as a open city, but now it is a dungeon