Thierry1030
"But you probably know that the wall inside the hotel hall is a fake one, not the real city wall, and it is not really where the original wall used to be."
-> if I remember well a guide tour with Brukselbinnenstebuiten the actual fake (?) wall in the hotel has been reconstructed with 'original' stones of the city wall, but it is true that the actual location is not where it used to be ...
taking that into account I would go for historic=citywalls and tourism=attraction and add a note that the 'location' is not authentic ...