Is that the on the day walk-up fare? Incidentally I'm 25 if that makes any difference.
I read that to break a journey you have to get a special 'via' ticket - is that only on domestic journeys then?
There are cheaper international fares for under 26s (15.50). It makes no difference whether you book in advance or not if you don't use Thalys. You can buy the ticket from the ticket machines in any station in the Netherlands. If you use a UK bank card, you have to pay a 0.50 euro surcharge. (On the NS International site, it says you can only use euro coins or Dutch bank cards. That is now out of date as they now accept Visa and Mastercard). There is no fee for using euro coins (notes not accepted). You can also buy it from the ticket office on the day, but there may be a booking fee for that.
There are no specific domestic discounts for under 26s in the Netherlands AFAIK, although students get nationwide free travel either on weekdays or weekends. In Belgium, under 26s can get a Go Pass 1, which is any distance one-way for 6 euros.
Via-tickets are for domestic fares in Belgium. I have to admit, I always assumed they were only if you wanted to go off route and not want to buy 2 singles, but looking at the website, it may be needed for break of journey.
