The Gwernyfed estate is of ancient origin; it is reputed to have been given by
Bernard de Neufmarché (), the earliest of the
Norman marcher lords, to Peter Gunter. It came into the ownership of the Williams family at the end of the 16th century. David Williams (d.1613), made his fortune in the law, serving as
attorney general for South Wales from 1581-1595,
Recorder of Brecon 1581-1604,
Serjeant-at-law in 1593 and a judge of the
King's Bench in 1604. His earnings funded extensive land purchases including the Gwernyfed estate which he bought from John Gunter in 1600. He also built up a substantial estate centred on
Kingston Bagpuize in Oxfordshire where he died in 1613. Subsequent generations of his family served as
members of parliament and as
High sheriff. In the 17th century, the original medieval manor house was rebuilt. It contains a
screens passage on which
Charles I is said to have left a coded message for
Prince Rupert of the Rhine when the king stayed at the house after the
Battle of Naseby in 1645. Charles was the guest of Sir Henry Williams (c.1603-c.1656), a staunch
royalist on whom the king had bestowed a
baronetcy the previous year. A later Williams,
Sir Thomas Williams, 1st Baronet, served as doctor to the king's heir,
Charles II. A major fire gutted the main wing of the house in the 1680s, and this remains ruinous. In the 1730s, the Williams moved their main residence to
Llangoed Hall and the old mansion descended to the level of a farmhouse. The baronetcy, and the male Williams line, ended with the death of
Sir Edward Williams, 5th Baronet in 1804. The estate passed to his daughter, Mary, and on her marriage to
Thomas Wood passed into their possession. In the 1870s, the family returned to the Gwernyfed estate, commissioning
William Eden Nesfield to build a new house, Gwernyfed Park, about 1 km north-west of the ancient manor, as a wedding present for
Captain Thomas Wood. Since the 1950s, Gwernyfed Park has been the main building of
Gwernyfed High School. After a period as a hotel, ==Architecture and description==