Circular room on the cover

[GKJPO]

No: HPFGUIDX 54324

As I was going through GoF (for the gagillionth time) last night, the 
word "circular" caught my eye.  There's been a lot of speculation on 
which is the special room that Harry doesn't know the magical 
properties of yet and there's a picture of a room on the American 
version of the cover.  Are they the same?  I don't know, but it 
looked to me like the room on the cover is circular, so I started 
going back through and identifying the circular rooms mentioned in 
the book.  I found the following:

- The Gryffindor common room
- Dumbledore's office
- The Divination classroom (the room, the tables and the trapdoor are 
circular)

I looked back through the references to these rooms and noted that 
none of them mentioned having other doors in them (like you see on 
the cover) or candles there on a regular basis though I would guess 
that the common room would have the doors to the dormitories. 

I think each of these rooms has great possibilities.  The common room 
and Dumbledore's office have connections to Godric Gryffindor and if 
the Chamber of Secrets is any indication, Godric will also have left 
behind a magical area he created.  These two places seem like the 
most likely candidates.  The Divination classroom is also a very 
interesting place for Harry as he always seems to have visions or 
encounter others having visions there.  I think it may be one of 
these rooms on the cover.

Another point of interest:  there are no circular references to the 
room behind the Great Hall where Harry goes in Book 4 (after being 
chosen and to greet the Weasleys.  This room has been suggested as a 
special place, but I found the description other than the mention of 
the witch Violet to be lacking.  A scant description to me means that 
the room has no special meaning as JKR seems to put special effort 
into describing and repeating several times throughout the books 
areas that are important.

The other place I investigated was the room where the Deathday party 
was held.  This room had the candles for the party, but no circular 
properties.

Does anyone else have thoughts on which room is on the cover?

Kristen