This is the thread we'll use if/when the Doorway which was hidden beneath the covenant is ever opened...
Overview: A small stairway beneath the ruins of an old tower led to a chamber of wards, and beyond it a large room with an inscribed archway in the centre. The wards have been investigated as an enchanted device which can be simplistically programmed using the tile positions.
The main chamber is very large, with an observation gallery above the main floor where the archway is set. The archway is surrounded by similar looking ads to those used in the outer chamber, and also is "filled in" by bars and wooden insets. This could be said to be a closing of the archway.