As lovely as any air-conditioned building can be, the chance to take some time out and enjoy the summer holidays in Japan is definitely welcome.
But it's a peak time to go anywhere. Flights and bullet train seats aren't cheap. Taking an overnight bus doesn't appeal. Luckily, in summer you get the chance to try something different: a Seishun 18 train ticket.
The Seishun 18 ticket
You can get a Seishun 18 ('youth 18' - there's no age limit though) pass from any JR train station that has a 'Midori no Madoguchi' ticket window. Not all of them do, so pick a major station to be on the safe side.
The availability and validity periods of the ticket vary every year, check that link for details in English. It's typically on sale for a month in spring and winter, and 2 months in summer. You can buy a Seishun 18 a couple of weeks before it becomes valid.
It's valid for travel on up to 5 non-consecutive days within the given time period, between stations in the open zone specified by JR. You can use it on consecutive days if you want! It's okay to split the days between different people, or for up to 5 people to travel on it together.
Be careful: a 'day' of use is midnight to 23:59. If you're on a late night train and it gets past midnight, it's classed as using the following day's ticket as well.
The catches, or the unique selling points, of the Seishun 18 are:
You can only take JR trains or the JR West Miyajima ferry.
Those can only be local, rapid, or special rapid trains.
You can't reserve a seat.
No bullet train, no limited express, no overnight sleeper trains, no 'green' reserved cars with more space. No buses! That makes it very different to the Japan Rail Pass.
Turning a train ride into an all-day adventure
I once used the Seishun 18 to get from Osaka to Tokyo... and back again. Yes, that sounds crazy. That journey takes several hours on the bullet train, and that's one of the quickest options. So limiting myself to much slower local and rapid trains was a pretty crazy idea.
One way, it took just under 10 hours with a Seishun 18, including changing trains (8 times!). Call it 9 and a half hours. If you set off from Osaka after breakfast, you'd be in Tokyo in time for dinner.
For some people, this isn't an option. Imagine coming to Japan for a week, and losing nearly 2 days of that in transit. It's more suited to people who have the spare time, who don't mind taking the scenic route.
It can make more sense to use a Seishun 18 for longer trips, considering the price. Compared to the usual cost for taking all those trains, by the time you get halfway back to Osaka it'll have paid for itself. With 3 days left on the ticket still to use at that point, that's seriously good value.
Lunch and loo breaks, right on schedule
Unlike many trains in the UK, long-distance trains in Japan (the ones that aren't bullet trains) tend not to have toilets on board. When I made my trips, I had to plan changeovers that gave me enough time to run to the loo and back.
Lunch is another consideration for an all-day train trip. It needs to be something you can eat on the move, and without a tray table built into the seat in front.
It's been a while since I've had to plan a trip with such precision. It's sort of exciting.
There's something about perfectly timing a change of trains that's really satisfying. That slide into the carriage moments before the doors close, not frazzled but smooth and relaxed. (I hate running.)
See more of Japan in summer with a Seishun 18...?
What do you reckon?