Tokyo's Shinjuku train station is the world's busiest with an average of 3.64 million passengers daily.
It has more than 200 exits, and, having passed through it twice in a day recently, I can confirm that it's not easy finding the right one, even with electronic help. It's the equivalent of trying to escape a maze while working on a Rubik's cube.
It goes without saying that the place is enormous and very busy. But there is also order and discipline which is how it is able to work so efficiently.
It also features images of the All Blacks on various walls, including a large-scale picture of halfback Aaron Smith — tattooed arms prominent — a reminder of the team's profile here and perhaps, too, the opportunity coach Steve Hansen's men have over the next six weeks.
There has been a lot of talk about the openness of this World Cup, but realistically probably only the All Blacks, South Africa and England are true contenders for their depth, experience and ability to cope with the cloying pressure of the knockout stages.
Even so, should the All Blacks win the final on November 2 it would have to rank as their greatest World Cup achievement; more so than their victories in 1987, 2011 or 2015.
It would also take their international reputation to another stratosphere.
Hansen has spoken often about the ability of his players to rise to a challenge — that was partly why they lifted their level of performance so markedly for the knockout stages of the last World Cup — and, as they start their defence with a first pool match against South Africa in Yokohama tomorrow night, it doesn't get much more challenging than this.
But, like four years ago, you get the impression there is more to come from the All Blacks — more than we have seen so far this year and certainly more than we saw from them in Wellington the last time they played the Boks.
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Not surprisingly, they were bitterly disappointed to concede the converted try which allowed the South Africans to draw that test in July.
It came about partly because Smith thought twice about leaping for a high ball for fear he would be "smoked", as he put it, by the hard-charging loose forward Pieter-Steph du Toit.
Smith this week confirmed he would never allow that to happen again; he would gladly put his rib cage in harm's way for the betterment of the team (in fact, he proved it during the recent Bledisloe Cup test at Eden Park when he was put in a similar position by opposition halfback Will Genia and safely defused the threat).
Meanwhile, at the Cake Tin, coach Rassie Erasmus and his men celebrated like they had won. This week that theme continued. Erasmus said several times after announcing a similar line-up for this match — openside flanker and skipper Siya Kolisi is the only change from Wellington — that they "won" that match.
One suspects they will need to improve significantly to win for real tomorrow night because the All Blacks, written off by many at home and overseas as a team in decline, will be determined to attack the Springboks in a way the opposition haven't seen before.
Get it right and they will be on the right track for a repeat against the old foe in the final in Tokyo in six weeks; a bullet train journey to sporting immortality.
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