It wasn’t a rock, because Ankh-Morpork was on loam. It was just some huge remnant of mortared masonry, probably thousands of years old, from somewhere in the city foundations. Ankh-Morpork was so old now that what it was built on, by and large, was Ankh-Morpork.
It had been dragged into the centre of the plaza, and Lady Sybil Ramkin had been chained to it. She appeared to be wearing a nightie and huge rubber boots. By the look of her she had been in a fight, and Vimes felt a momentary pang of sympathy for whoever else had been involved. She gave him a look of pure fury.
Lady Ramkin is brilliant.