Room 234-00

Room 234-00 is the room where Argus Filch lived in Hogwarts Castle. It is connected to the Entrance Hall, on the Ground Floor of Hogwarts Castle. It's a small, simple room with a single oil lamp hanging from the ceiling. It smells vaguely of fried fish. There are filing cabinets in it with details of the misdeeds of Hogwarts Students. Fred and George Weasley have an entire drawer for their own misdeeds. One of those cabinets are full of confiscated magic items marked "Confiscated and Highly Dangerous", in which Fred and George found the Marauder's Map. Filch kept his chains and manacles in this office (it's common knowledge that he always begged Dumbledore to allow him to hang students by their ankles as punishment), and kept them well polished.

Due to the office being owned by Filch, who is disliked by every student in Hogwarts, the students tended to avoid it at all costs. Harry, during his second year, was called in for punishment after tracking mud into the castle, and found a Kwikspell letter in this office, which eventually lead to him finding out Filch was a Squib.