Cheesemonger's Hollow is a part of the Shivering Isles. The Vestige is sent there by Arch-Mage Shalidor in the Second Era to recover some tomes that had been stolen by Sheogorath, the Daedric Prince of Madness.
The hollow is both a beautiful and grim place with the vegetation, lava falls and Sheogorath's minions protecting the place. At the bottom is a large temple like building where Gutsripper is protecting the four tomes his master have stolen.
A high-ranking member of the Mages Guild, Valaste wants the Vestige to perform a task for her. They must find a ruin nearby, which Valaste says may hold a store of ancient knowledge.