What can you tell me about the Hotel Du Chateau?

If I'm not mistaken, the Hotel Du Chateau is just adjacent the old Cite walls, no?

If that is the one than it has a very good reputation for service and ammenities, albeit I haven't stayed as a guest.  

The location cannot be better,the entry gate to La Cité Médiévale must be just a few minutes away.  

The newer city or Ville Nouveau will then be 15mins walk over the Pont Neuf so very close. Carcassonne is a small walkable town with excellent restaurants and historical sites.  I think the location of the hotel cannot be better!

In case you are looking few more recommendations, on restaurants and landmarks, checkout my Carcassonne blog post:http://www.aforkinlondon.com/post/89990427830/carcassonne

Hope this helps!