NS Group Ticket: They also have great tickets for you tourists out there! Kruidvat is a chemist chain with stores in most towns and cities of the Netherlands. Book train tickets with zero service charges on Confirm Tkt Applicable to all users.
For example, they sometimes put on deals where you can get transport and entry fee all paid for in one, so remember to keep checking the site!
Applicable twice per user. At the time of writing, the tickets can be used before or on September 30, They need an OV-chipkaart in order to benefit from the cheaper rates afforded to the locals. Just keep in mind that this is a train ticket thus not valid for busses, trams or metros.