Hay-on-Wye in Hay is a sub-office of Hereford, and therefore although in Wales has an English postal address, being part of the HR3 postcode. Hay-on-Wye is a Welsh community with a Town Council. Its boundary follows the English border/Dulas Brook from the River Wye southeastwards for just over a kilometre, turns south-west to a point just south of Oakfield house, thence north to Greenpit Farm and north westwards, enclosing the Hay Showground and meeting the National Park boundary near the B4350, Brecon Road. From this point, it follows the National Park boundary to the River Wye and the river back to
England–Wales border their areas formed into new counties, or amalgamated into existing ones. At this point, the boundary between England and Wales, which has existed ever since, was effectively fixed. In the border areas, five new counties were created – Denbighshire, Montgomeryshire, Radnorshire, Brecknockshire and Monmouthshire – and Flintshire gained some additional territory. However, several of the marcher lordships were incorporated in whole or in part into English counties. The lordships of Ludlow, Clun, Caus and part of Montgomery were incorporated into Shropshire; and Wigmore, Huntington, Clifford and most of Ewyas were included in Herefordshire. According to John Davies: Thus was created