Seishun 18 Kippu

The Seishun 18 Ticket (青春18きっぷ, Seishun Jūhachi Kippu) is a special discount ticket issued in Japan which allows holders one-day unlimited rides on the local trains of Japan Railways Group during limited periods of year.

One ticket is valid for five (not necessarily continuous) days (midnight to midnight), within the designated period of the season (see table below for seasonal periods). It can also be used by several people simultaneously; for example, five passengers can use entire one sheet of ticket for their one-day trip as a group instead of one passenger traveling individually on five different days. Basically a single sheet of ticket can be stamped for up to 5 times, and a single stamp means unlimited travel for one person for that day. The price of the ticket is 11,850 yen per sheet of 5 tickets, this means 2,370 yen per ticket. This ticket is ideal for long distance travellers, wherein people can get more value for their money.

In the context of Japan Railways Group, the term "local trains" (普通列車) means not only trains that stop at every station, but also all passenger trains except for Shinkansen, limited express and express trains that require express surcharges. This ticket is meant for travel on "local" (普通, futsū) or "rapid" (快速, kaisoku) train services.

There is no age limitation, despite the name "Seishun 18" (literally "Youth 18"). The ticket cannot be used in automatic ticket machines, even though the back of the ticket is magnetized. This ticket is not available at standard ticket vending machines, but during the on-sale period it can be purchased from the higher-end machines (that also sell Shinkansen tickets) under the heading "O-Toku na Kippu". it can also purchased over the counter at JR train stations or a travel agency during the on-sale period.

Each year the ticket goes for sale on three different occasions, details are shown in the table below. Although every season the JR authorities quote that these dates are subject to change, however over a long history (since year 1982 when this ticket was first introduced) these dates have remained unchanged and can be considered as a standard data. Note that once a ticket is purchased, it can be used only for that particular season. JR can refund full money only for tickets that remain unused (not stamped) before the end of the "Tickets on sale" period.　

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Wikipedia