The two mice made their way gingerly down the secret staircase.

"It contains a secret staircase that provided a private way to his chambers."

And I believe there's a secret staircase as well.

"How did you find out about this passageway and the secret staircases?"

A secret staircase that goes down inside the wall.

The bottom of the secret staircase ended in a blank barrier.

The tower also included a secret interior staircase - a source of great fun for his young sons.

"There's the door to the secret staircase," he said.

Any of them could have hidden a secret staircase.

Harry immediately led the way down the secret staircase and out through the passageway into the alley.