The field system and a building are shown at Disgwylfa on the 1" to 1 mile Ordnance Survey map of 1833, although it is not named. On the 1st edition 1:10560 Ordnance Survey map of 1891, the main building is shown as a long rectangular building on the east side of a yard and parallel to the road. By the time of the 2nd edition map a square building NPRN 242375 had been added. This square building is now used as a conservation centre by the MoD. J.J. Hall, Trysor, 2 May 2008