It was shortly after nine on Saturday morning when the hordes began to spill from the commuter trains, through Kaihimmakahuri station and across to the imposing Makahuri Messe convention centre which was playing host to the annual Tokyo Game Show.
The Messe spreads out over close to 900,000 square feet yet, it looked as if the flood of humanity snaking towards it would cover every available inch. By 11am, the flow had barely eased, if at all.
Here, in one long snapshot, was a sense of the scale and a glimpse into the culture that make Japan what it is.
The Irish team will have seen little of that.
Their hotel looks out on the route the thousands traversed last weekend but Joe Schmidt’s squad were busily preparing for the half-hour bus ride to their training ground while all this was unfolding.
It begs the question as to just how much players get to soak in when touring a country. Do their surroundings, beyond the lobby, affect them at all?
“You learn when you’re at World Cups, or on Lions tours, or Irish tours down to the southern hemisphere, that it’s definitely not a holiday,” explained Tadhg Furlong before the team’s arrival here last week.
Routine is a player’s best friend. That extends to the food they eat to the pillows on their beds. The IRFU and Schmidt’s backroom staff will have left nothing to chance in that regard. Actual contact with the locals, regardless of location, is pinched by the rigours of training, the need for recovery and a myriad of other duties.
The Irish players will be greeted by the painfully polite lift attendants and other hotel employees but the chances of actually experiencing something of Japan beyond the front doors will be few and far between.
Does that matter? Yes, it does.
Ireland’s players have been in training, a particular form of quarantine in itself, since June for this World Cup. They need distraction and stimulation beyond the day-to-day.
“It’s so important that they embrace it,” says Bernard Jackman. He should know. Jackman studied Japanese for two years in university and has friends who live over here.
The former Leinster hooker toured the country with Ireland in 2005 when a day trip to see some temples was among the outings that took their mind off rugby for a spell and allowed them to appreciate their surroundings.
“The thing about Japan is you go out of your hotel and turn left or right and it’s so different. So many places in the world have become so westernised whereas, while it is getting more westernised in Japan, you do feel you are in a different culture. There are not as many Starbucks, Burger Kings or McDonald’s.
"There’s great street food and Japanese tea and how they serve it. All of that.”
Every team will have its ideas on when and how to strike that balance between focus and freedom.
The South Africans were the first to arrive for this World Cup and Rassie Erasmus summed up how something as mundane as the switch from regular city buses to tournament-branded coaches can make the hairs on your neck stand.
Captain Siya Kolisi was among a troop that went to see the Sakurajima volcano just outside the city and it gave a rumble on arrival.
Not all excursions will be rewarded so richly but Bryan Habana, who visited Japan for the first time in the summer, is of the opinion that such an openness will be rewarded on the pitch as well as off it.
“Logistically, it will be unique as a World Cup and, as foreign as that experience is, each team will have to overcome and embrace that so that their on-field performances are not affected,” says the 2007 World Cup winner.
“The team that adapts to that, that will overcome those challenges from the time they arrive, will stand a chance to do very well.”
Getting to grips with Japan isn’t easy. Patricia Heberle is the chef de mission for the Irish team that will compete at next year’s Olympics in Tokyo.
The Australian has already made at least four planning trips to the capital and Shizuoka where many of the athletes will spend time pre-Games and she admits that it took her time to get to grips with the dos and don’ts.
There are no half-measures here.
The Irish attitude of things being ‘grand’ on the night doesn’t cut mustard in Japan.
Meticulousness is the norm and offence is taken if short cuts are sought. Joe Schmidt should be very happy here, basically. The concept of respect and the importance of etiquette is evident every time a waiter hands you your change.
The Japanese eschew physical contact too. Bowing is the norm.
“There are little things,” Heberle explains.
“You will never hear a phone ring on trains. They have to be on silent and you will never hear them talking on the phone on public transport. It is illegal, you will get fined. That’s very different to most western societies. The taxi doors are automatic and they don’t have a lot of rubbish bins.
"It is just a completely different experience. Most big train stations have arrows and you have to walk in that direction. It’s so regimented. That’s how they move millions of people on public transport every day.”
That’s a lot to remember for your average Paddy on the street, let alone a player who has any amount of strike moves or lineout calls knocking around his head. Ultimately, though, the only adaptation that will matter to the wider public is the team’s ability to think on its feet within the white lines.