AHA! An oubliette. I know this one from The Labyrinth.
<span style="color:#323232;">Hoggle : This is an oubliette, labyrinth's full of 'em.
</span><span style="color:#323232;">Sarah : Really. I didn't know that.
</span><span style="color:#323232;">Hoggle : Oh don't act so smart. You don't even know what an oubliette is.
</span><span style="color:#323232;">Sarah : Do you?
</span><span style="color:#323232;">Hoggle : Yes. It's a place you put people... to forget about 'em!
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