I was thinking of the wardrobe and the east cellar, in Twilight.

But that reminds me of two more.

Arkham crypts (ish) if you go down from Arkham, then all south and then West.

And ktengs. The one with the faces in it. I think that one is where you can end up on the wind side of it. Makes me wonder, though, whether ending up on the wrong side might be survivable, and you then exit through that door, back into the gallery.