We look back on some our favourite clashes between the two rivals
Ireland and Wales renew old rivalries today with many hoping for the latest installment in a long line of classic encounters.
Below, we break down some of our favourite Six Nations encounters between the two before the kick off on Sunday.
Where else to start but the game that delivered Ireland's first Grand Slam in 61 years in the most dramatic of fashions.
An instant classic, the events that unfolded at the Millennium Stadium that day have gone down in rugby lore as some of the most gripping action to grace a rugby field, with superlatives for the game long been exhausted.
Who can forget the sequence of second half events that ensued: two quickfire tries, a drop goal, a 'manky' drop goal and then a short kick resulting in Geordan Murphy gratefully clutching the oval ball to his chest before hoofing it into Row Z, as Barnes to gave a shrill blast of his whistle to indicate full time.
If Wayne Barnes was a friend to Ireland in 2009, he was public enemy number one following Wales' last gasp victory in Croke Park.
The English ref adjudged that Stephen Ferris illegally tipped Ian Evans into the ground and duly awarded the penalty which was swiftly followed by a yellow card for the blindside, before the metronomic Leigh Halfpenny stole the win.
Ireland's grievances were well founded, particularly when Barnes felt that Ferris' tackle and Bradley Davies' off the ball spear were worthy of the same punishment.
It was another stunning game of rugby in the 78 minutes prior to the incident, with blows being exchanged right throughout.
Johnathan Davies grabbed a try either side of a Rory Best effort, with his second being particularly memorable: George North swatted away Fergus McFadden before giving a sumptuous offload to send his compatriot clear.
Tommy Bowe crossed in the corner to swing the game back in Ireland's favour with 15 minutes to go, but ten minutes later North touched down, taking two defenders with him on his way, leaving the score at 21-20 with the late drama yet to unfold.
Ireland's Six Nations campaign veered badly south after a thrilling victory in Cardiff, with some scintillating rugby on display.
Ireland obliterated defending champions Wales in the opening half, leading 23-3 at the break following some breathtaking rugby, including an adroit Zebo flick.
The Munster wing dotted down following a gorgeous fade and pass from Brian O'Driscoll before Cian Healy barreled over after Zebo's innovative play kept an attacking move alive.
Sexton was in form with the boot, nailing the two touchline conversion and tacking on three penalties in the first half.
O'Driscoll then broke the Six Nations try scoring record with his 46th international try and the competitions 26th before Wales launched a spirited comeback that fell just short.
Alex Cuthbert went over first with Halfpenny grabbing Wales' second after Best was binned. Ireland managed to hold out however, despite seeing Conor Murray binned and conceding another try late on.
The second half collapse was a sign of things to come for Ireland, as they finished fifth, failing to win another game in that years tournament.
The Welsh once again crushed Irish hopes of a Grand Slam after they played out a pulsating contest in Cardiff.
Far from free flowing rugby, this game lives on in the memory for an incredible defensive effort from Wales as Ireland set up camp in their 22' for the majority of the game.
Gatland's well drilled unit physically battered Ireland in the opening exchanges, and took a 12-0 lead before Johnathan Sexton brought Ireland back into it with two penalties of his own.
A chink in the armour seemed to appear when Sam Warburton was binned, but Ireland couldn't take advantage as Sexton and Biggar traded scores to make it 15-9 at the break.
The second half saw how brutal the Welsh defense could be as they withstood a barrage of pressure from Ireland without conceding, before Scott Williams widened the gap with a try.
Ireland did finally break the Welsh resolve when they were awarded a penalty try, but another Halfpenny score put seven between them. Despite having Johnathan Davies binned late on, Wales survived the late assault on their line.
Wales ended their 28 year wait for a Grand Slam when they defeated Ireland 11 years ago in another game of high drama and talking points.
Gavin Henson was at the peak of his powers at the time, and he weighed in with a drop goal and long range penalty to add to Gethin Jenkins' first half try.
Ireland were behind 29-6 after two more Stephen Jones penalty and a Kevin Morgan try, but they showed their fighting spirit with Marcus Horan and Geordan Murphy getting over. However, it proved to be in vain as Mike Ruddock's Wales secured the Grand Slam on home soil.