Hill and promontory enclosure near Merthyr Cynog.

Hugh Thomas's eighteenth-century folk-tale places the martyrdom of Cynog on a hill called 'the Vann' above Merthyr Cynog. This hill, now labelled 'Corn y Fan', with farms Fan-Uchaf and Fan-Isaf on its slopes, is probably the place imagined, and this may also be the site of a holy well.