The 1971 tour will live forever in the hearts of rugby lovers worldwide.
The Lions success was built on the form of the Welsh Grand Slam side of 1971, but the rest of
the Isles contributed players of the quality of Willie John McBride, Gordon Brown and David Duckham.
Under the astute leadership of coach Carwyn James, the Lions mix proved intoxicating and unstoppable.
After a 58-hour flight to Australia the tourists were quickly asked to play two games.
They unsurprisingly lost to Queensland before struggling to victory over New South Wales.
This prompted Queensland coach Des Connor to describe them as the worst Lions team ever to be sent to face New Zealand.
The New Zealand leg of the tour started with four wins for the Lions, but it was the 47-9 hammering of a powerful Wellington side that really showed they meant business.
A rough ride was expected in Dunedin - the home of the ruck - but, with David Duckham on top form, Otago were beaten 21-9.
Canterbury proved a tougher proposition in Christchurch, the Lions winning a brutal game 14-3
but suffering injuries to key personnel.
Shrugging off the bloodshed, the Lions won comfortably against Marlborough and Nelson Bay and kept the momentum going in the first Test, winning 9-3 in Dunedin.
The next three games were also successful, but the tour was far from over and a fired-up New Zealand claimed a 22-12 win in the second Test in Christchurch.
Barry John in action on the 1971 tour
The performances against the provincial sides revived spirits, Gerald Davies finding the peaks of his considerable powers to run in four tries against Hawke's Bay.
With confidence restored, the tourists were able to take the third Test in Wellington 13-3.
As the tour drew to a close, the Lions were able to maintain their impressive, undefeated
form against the provincial teams, but everything was building towards the final Test.
The two sides battered each other to submission, resulting in a remarkable 14-14 draw in Auckland - and a series win for the Lions.
This was the first British or Irish side to win a major series abroad in the 20th century and, at home, it was greeted with jubilation.