Not even the FIFA World Cup in South Africa (average crowd 49,670), nor its rugby equivalent in France (47,376), could hold a candle to it in terms of box-office appeal.
The Tri-Nations fell just short of 50,000, the new-fangled Indian Premier Cricket League reached 58,000 and America's National Football League came closest at marginally more than 68,000.
The UEFA Champions' League finished some way down the list last season at 43,108.
The Ashes series generated record gate receipts for Cricket Australia and yet the average daily crowd for the five Tests barely amounted to 35,000, half the Six Nations figure.
Commercially, the numbers keep on going up at such a rate that the 2011 championship will generate around £320m.
Far from creating an imbalance on the field, the tournament has restored its glorious democracy as never before.
Over the last twelve years, everyone, bar Italy, has won the title at least, Wales twice pulling Grand Slams out of the blue and Ireland once while England have been enduring their longest run without a prize since their bad old days of the Eighties.
The Six Nations' gross value has more than doubled in eight years, an exponential increase which has been supervised by a 47-year-old Dubliner whose ability on the tighthead of the Old Wesley scrum earned him international recognition for Ireland at schoolboy and under-21 level without quite extending to what was then the Five Nations but John Feehan is living proof that front row forwards can chew gum and think at the same time.
Appointed chief executive of the Six Nations within six months of joining in April 2002 as commercial director, he took charge at a time when the grand old tournament appeared to be in some danger of shrinking into an Anglo-French monopoly.
"Some people were wondering whether the championship was on the way out," he says.
"Some people, without any names being named, felt that, somehow or other, it would always be dominated by England and France.
"You couldn't possibly put that argument forward in the light of the last five or six years with Wales and Ireland doing Grand Slams.
"If anything, it is more vibrant now than it has ever been. The essence of sport is its doubt.
"When you know the result, it's boring. Quite frankly, I don't have a clue who will win this year's championship. I can't remember it being so open which is fantastic."
A graduate in management studies from Trinity College, Dublin who worked in sales and marketing for several multi-national companies before he began driving the Six Nations ever upwards, Feehan has witnessed 'huge growth' in its appeal.
"Our television audience in the UK five years ago would have been about 46 million," he added.
"Last year it was nearer 64 million. We have delivered better television audiences and better television deals. The Unions have put all that together, each buying into the joint ownership of the championship and that's why it has become so successful.
"We've had significant increases in our broadcasting and sponsorship revenue. Each of the individual Unions has made huge contributions by improving their ticketing and hospitality. That, inevitably in a tough economic climate, has taken a dip but our stadia will continue to be filled to capacity.
"The new media development has been huge. Last year we had 5million people downloading snippets of the tournament as well as more than one million watching it live on broadband.
"And while all that's been happening, we've lost none of our television audience.
"On top of that, there continues to be an unprecedented level of press interest. Over a four-year cycle, the Six Nations is worth more than 1billion sterling - three times more than the World Cup.
"In that respect, it is delivering an enormous amount of money into the game in the Northern Hemisphere which is distributed relatively evenly amongst the six competing countries."
The Six Nations has always been not merely a series of matches but a colourful collection of social and cultural experiences.
It has a mystique an an historic dimension other tournaments can but dream about which is why fans move by the tens of thousands to follow their team on a biennial pilgrimage widened at the turn of the century to include Rome.
"You could say that, in some other championships, teams over-play one another," Feehan says. "That doesn't happen here. You only get to see your team play in London, Dublin, Paris, Edinburgh, Cardiff or Rome once every two years.
"Most of the scheduling is based around delivering a better product for the fans. With the stadia full, the only way we can get more fans to see the Six Nations is through television or new media with the result that millions more are accessing the Championship. It's very important we do that at a time when people want to watch it."
This year, for the first time, it all kicks off on a Friday night, in Cardiff for Wales-England.
The two previous Friday night experiments, France-Wales in Paris two years ago and the return fixture in Cardiff last year, attracted abnormally high viewing figures in excess of ten million.
"We try to strike a balance between what's good for the fans who attend the games and what's good for those who watch it at home," he says. "Five years ago we had 25million less people watching our championship than we have now which is good for rugby and good for the development of the game."
"Outside the World Cup, this is the most widely distributed rugby event on the planet which is available in more countries around the world than ever before - 139."
Perennial calls from some quarters for the event to be relocated to the end of the season will fall on deaf ears and rightly so.
"This is a seven-week championship played over five weekends which delivers one third of the revenue for rugby in the Northern Hemisphere," Feehan says.
"Why would you risk messing with your most important item by putting it back to a time when it would up against the French tennis open, Grand Prix, Test cricket and the culmination of all the soccer finals at home and abroad?"