The entrance to the basement is in the most out-of-the-way part of the library, where the oldest books are shelved. Amidst the dust and crumbling pages, there is a door quite hidden until one gets close. The door is locked, but the mechanism is so old that it sometimes fails under pressure.

After a long and winding staircase, there are some anterooms with even older books on rickety shelves. And after that there is the basement proper. It is riddled with ancient booby traps (which don't always work), doors that disappear and reappear, and various amounts of decay. Its maze like design has made it quite perilous to enter, but the promise of secrets and adventure has lured many down here.