Glanhirin is shown on the 1833 1 inch to 1 mile Ordnance Survey map as a building and a long straight rectangular parcel of land to the east and a field beyond. On the Llansanffraid Cwmteuddwr tithe map of 1841 it is shown as two fields, Bryn Bychan and Bryn Llwyd, with the building external to Bryn Llwyd. By the time of the 1st edition map of 1891, the two fields have been subsumed into a larger, more rectilinear field system, closer to the field system in existence today. The fields are in 2009 are defined by post and wire fencing and still in use. J.J. Hall, Trysor, 31 January 2010