Madame Pomfrey's office.

[kritchen]

What floor is the hospital wing? I just want to see if there actually is a set floor for it.

[cmwinters]

Well, it seems to move; it was on the first floor initially but then moved to the third.

http://hp-lexicon.org/hogwarts/castle/hogwarts_inside.html

[kritchen]

Thank you. I thought I read somewhere that it was on the third floor. Plus reading that gave me some ideas for plot bunnies so a double thank you. :]