A limestone quarry at Twyn Disgwylfa was probably opened in connection with the adjacent 1820s Brecon Forest Tramroad (nprn 406399). A bank of limekilns (nprn 80196) stood on the west side between the quarry and tramroad. The site was marked as 'Old Quarry' on the second edition of the Ordnance Survey 25in map of 1905; however, the workings have largely been removed by modern quarrying activity.
B.A.Malaws, RCAHMW, 10 February 2009.