Here is the map of fictional Academy of the Anchor Accords, originally drawn in pencil and overlayed in Photoshop with some lovely straight lines and doors.

Classrooms on the left and student dorms on the right. Admin and janitorial in the center.
Secret doors can be found throughout the Academy from staff wanting to avoid students, students wanting to avoid teachers, and everyone wanting quick shortcuts. There’s also a hidden room where the staff hide the good stuff! (booze? chocolate? magic items?)
Is this an abandoned building? An active school? You decide!
The Anchor Accords is part of an idea I’m toying with for a new campaign that involves time and space magic and what happens when one of the dimension’s anchors is removed by some foolish adventurers.