The castle exterior.
Guinevere’s House is, as its name states, the home of Guinevere. It only appears in a deleted scene of Shrek the Third called "Cyrano de Artie".
Only her bedroom was seen in full in the storyboard. It was likely to take on the appearance of a typical teen girl room. Another resident of the house is a girl named Jessica, who willingly lets boys into the house despite the assumed disapproval of their guardians.