This compound literally means “blue/green spring," close enough to its actually meaning – “youth.” It’s used all over the place, notably in 青春１８切符 – the Youth 18 Ticket, a special Japanese train ticket that gives you five days of unlimited rides on local trains. While the title of the ticket includes both “youth” and “18,” anyone can use the ticket. It’s only available during school holidays – summer (July 20 to September 10), winter (December 10 – January 20), and spring (March 1 – April 10) vacations.
The five days can be used non-consecutively, but you have to ride local trains – i.e. trains that don’t require a 特急券 (とっきゅうけん, express fee), so some 快速 are included. The best part of the ticket is that it costs a mere 11,000 yen, or just over 2000 yen per day! To be used effectively, though, it does require that you ride for hours on end, but, hey, get some beers and a bento and enjoy the ride.
Some of the special trains that are somewhat-limited-express are the overnight trains. I’ve only ever taken the Moonlight Kyushu that runs between Hakata and Shin-Osaka, but there are several others. The Moonlight Nagara has a stop that departs after midnight, which means you only need to use one of your five days (if you are on the train when it crosses over midnight, you’ll have to stamp twice…unless you’re lucky – video requires facebook membership).
Summer vacation doesn’t start for a while, but it’s critical that you reserve your spot on these overnight trains a month in advance (the reservation only costs an extra 500 yen…make sure to tell them you’re using the Youth 18 Ticket). They sell seats on these trains starting a month before departure, and they are extremely popular (especially the dates around the start and end of the New Years’ holidays); people line up to buy tickets at 5am on the day one month before they leave.
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