There have been 54 referees from Wales who have controlled international matches and Derek Bevan still holds the world record for the number of Tests he blew in - 44.
"We have always had exceptional referees in Wales and a number of them have been heralded around the world as the best in their time. But they have largely been unsung heroes," said WRU chief executive Steve Lewis, whose father Ernie picked up a cap.
"That's why, in the 125th anniversary season of the WRU, we felt it was about time we recognised the true Test status of our 54 international referees. There are 18 who are still alive and they will all receive an international cap to signify their achievements.
"Our referees and match officials group deals superbly with the recruitment, retention and development of referees. Theirs is never an easy task dealing with the often thorny issue of appointing match officials to both the community and elite game."
Among the 54 Welsh international referees there are eight who played for Wales (Charles Lewis, Horace Lyne, William Phillips, Billy Douglas, Tom Williams, Harry Bowen, Gwyn Nicholls and Tommy Vile); two who acted as treasurer of the Union (Richard Mullock and Williams Wilkins); one who was secretary (Richard Mullock) and five who became President (Horace Lyne, Tommy Vile, Wilf Faull, Vernon Parfitt and Gwilym Treharne).
More recently, Ken Rowlands, Clive Norling and Rob Yeman worked for the WRU in their referees departments.
Current internationals Nigel Whitehouse and Nigel Owens, who are among the 18 living Welsh Test referees, will be on duty at the 2006 RBS Six Nations championship. The 17 Welsh international referees who picked up their caps were Meirion Joseph (Cwmavon), Ernie Lewis (Abertillery), Selwyn Lewis (Cwmgors), Cenydd Thomas (Pontypridd), Corris Thomas (Cardiff), Alun Richards (Caldicot), Ken Rowlands (Ynysybwl),Derek Bevan (Clydach), Les Peard (Castleton), Gareth Simmonds (Taffs Well), Rob Yeman (Taibach), Clayton Thomas (Bryncoch), Robert Davies (Dunvant), David Davies (Llanbradach), Nigel Whitehouse (Gowerton), Nigel Williams (Bryncoch), Nigel Owens (Pontyberem).