If you look closely to the immediate right of the Cathedral, you can see the wires of the skylift. And below them, you can almost see the beginning of the staircase. We climbed the stairs (I learned later we could have driven up). There were 408 stairs, and about 1/3 of them had you parallel to the cliff-wall.
In the Citadel's museum, they have a replica of a carriage that Napoleon's mistress rode in when she came up from Paris and met him here (that would have been *before* Waterloo, I assume).