They can get pretty crowded, but I'm not sure if that'll be the case on January 1st. Usually a rather quiet day, but it being a Sunday might mean more people are heading home. Check bahn.de for indications on how crowded these will be.

For €4.50 you get a reservation all the way from Brussels to Zürich, booking through the German railways. Personally I'd reserve seats since it's quite a long journey and I'm not a fan of seat-hopping, but it obviously depends on how you value the certainty of having a seat. It's pretty unlikely you won't be able to travel, though, in my experiences.

Plan sufficient time in Frankfurt, as these ICE trains are also pretty unreliable lately. It's common for some to be cancelled, limited in their journey or considerably delayed.

These ICEs have optional reservations but they can still be very busy; in extreme cases of overcrowding passengers without reservations can be asked to leave the train. Currently, DB is already saying that both ICEs in this journey are expected to have high demand, so it's best to make a reservation. The best is to do that via the DB website (choose “Seat only”), where reservations are only €4.50 (€5.90 in 1st class) for the whole journey.

@rvdborgt Thanks, One more thing… Is 1hr 10Mins enough to catch the train from brussels to zurich from the same station?

@Schelte Thankyou, Is 1hr 10Mins enough for me to catch another train from Brussels to Zurich?

That should be enough - Eurostars are generally reasonably okay punctual, and the transfer requires no formalities - just walking to the other platform.

Note however it’s not a direct train from Brussels to Zürich but involves a change in Frankfurt; there you’ll have 35 minutes to switch trains. In theory, that is enough, but in practice trains have been far from punctual on the Brussels-Frankfurt route. Not much of a problem, as there still are a few later trains on that route, but be aware of it.

In case of delay of ICE 315, it may be faster to change at Frankfurt Flughafen (airport) in the direction of Mannheim/Basel. In any case, download the DB Navigator app to have realtime information in Germany and to check your options in case of delay.

@Schelte I am checking on Bahn website and it is costing me just 9 Euros for 4 passengers in reserving this route. I think it will be worth it than getting disappointed. thanks a lot and appreciate your time.

10 mins should be enough already. One more time: except that airplane-imitating €* all trains are not planes: they have multiple doors, no check-in, no left luggage, noone to welcome you-it is all self-service. All those from far over the oceans and not knowing how it works all seem to have endless fears about fullness-and seem unable to even fathom the answer: if really all seats are taken-or indicated as such, one STANds-just like in a normal bus. As there are also multiple stops at every such pax get off and on-giving new chances on empty seats.

ICE is also not a train-comp but just a type of trains -electric deluxe long-distance hispeed sets from DB, the main German state-owned company. They have 100s of these things in various formats. But as BE and DE have different electricity on the wires-only a few hybrids can do these trips-and that means there is no quick substitute if one set fails.

Also: DB has a kind of self-developed indicator on how full they expect a train to be-can see that on their navigator. They very well know that there are cheaper tix ONLY valid on a certain date/train and also FLex ticket-like your pass also is-and anyone an turn up with that without any pre-announcement. Sometimes they do indeed stop selling tix for a specific train, but even then it does not mean one cannot get on with other type of tix-again, its not an airplane-nor an IR always late limited ´express´ with 3d and 4th tier etc.

Indeed, for groups involving children family reservations are available. When travelling with children, reservations are really recommended - otherwise you’ll probably not end up sitting all together.

Bruxelles-Midi/Brussel-Zuid is the starting station of that route. I’ve newer known it to be full from Brussels on. Usually this is the case from Aachen, mostly Cologne.

If you head straight to carriage 22 of the ICE in Midi (for some reason that carriage is barely reserved) you’ll be able to find plenty of seats without any reservation - tried an tested for you, many times .