DanielB
Member
I'd presume staff in that region is well aware of international tickets, if you're checked at all as both don't have a guard on all trains but just spot checks.I've just spotted that RE18 is operated by Arriva Nederlands. RE4 is operated by National Express. That's got to complicate things. Is it worth chancing it or buying tickets for those and claiming them back or what?
The only issue might be when you want to cross the Netherlands with the RE18 with FIP, as those tickets are not valid at Arriva. However Liège - Herzogenrath is covered by the Euregioticket as an alternative that's not too expensive (should you be travelling in a weekend it's valid for up to two adults).
Sit on the right side for the best views from the Netherlands into Belgium by the way, RE18 is one of the more scenic Dutch routes.