Even though the cellar is not much higher in altitude than the dungeons, it is much more welcoming.
Includes the Hufflepuff common room & dorms and the kitchen.

This is the first floor you will see upon entering the castle; has a bright, cheery, and welcoming atmosphere.
Includes the Entrance Hall, Great Hall and Caretaker's office.

This floor is relatively quiet considering the fact that it is very close to ground level. It is, however, congested at least once a week, due to dueling practices.
Includes the Dueling Hall, Trophy room, and Moaning Myrtle's bathroom.

Many destinations on this floor are used primarily by members of the Hogwarts Staff, but students often pass through this floor's main hall to reach classrooms on upper floors or to visit the Headmistress.
Includes the Headmistress's office and Staff room.

More classrooms are located on this floor than any other, making the third floor one of the busiest areas of Hogwarts.
Includes the D.A.D.A. classroom, History of Magic classroom, Muggle Studies classroom, and Transfiguration classroom.

The Library is located on this floor of the castle, making it very popular amongst Ravenclaws.
Includes the Library, Arithmacy classroom, and Charms classroom.

This floor is home to Ravenclaw Tower, making it very quiet most of the time.
Includes the Ravenclaw common room & dorms, Animagi Studies, Astrology classroom, and Prefect's bathroom.

The main destinations on this floor are classrooms. It proves difficult for Slytherins and Hufflepuffs to reach this floor in time for their classes because it's so far from their common rooms.
Includes the Legilimency & Occlumency classroom, Mythology and Legend Studies classroom, Ancient Runes classroom, and Ancient Magicks classroom.

This floor contains the Gryffindor common room, and is therefore brimming with Gryffindor students. No classrooms are located on this floor, though.
Includes the Gryffindor common room & dorms and Room of Requirement.