Aspiring thieves come here to seek entrance into the guild and Armand Christophe, a Thieves Guild Doyen, is here. Armand can be found here around midnight.
After the Thieves Guild quest "The Ultimate Heist" is completed, the Guild's base will be found. The Hero will gain a key, and this allows them to use the hall as another safe resting place, as well as having lots of storage room.
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