The Secret Staircase in Jane Eyre
Via Mirabilis, we find this BBC article about the secret staircase that Charlotte Bronte refers to in Jane Eyre:
In Jane Eyre, the hero Mr Rochester keeps his mad first wife in a hidden attic up a secret stairway. The owners of Norton Conyers in North Yorkshire always believed their house near Ripon may have inspired the writer. But the staircase had been hidden since the 1880s and its current residents only found it after clearing the attic.
Ah, for the nineteenth century, when no one gave a second thought to keeping your crazy wife in the attic.