Question is which pass you hold? Global Pass? 

Note that Paris - Barcelona is very popular and only few trains per day on that Route You may look for a Plan B Route from Paris via Perpignan - Portbou to Barcelona 

Please give us the train number/route and we’ll be able to help better. It’s impossible that trains are sold out so far in advance but there might be other issues.

For example the international AVE trains run by RENFE are unavailable online. You may get reservations for them on the day on the platform but it’s a bit risky. You should look at alternatives.

(Hopefully the RENFE issue is solved one day...)

the precise train numbers are TGV 9826 which leaves Brussels Midi at 10.17am and arrives in Valence TGV at 2.45pm. the second AVI 9742 leaves from Valence TGV at 3.11pm and arrives in Barcelona at 7.34pm

i have Interrail Global Pass 2a classe

 AVI 9742 is not bookable online for passholders.

Okay thanks for the answer.

First train: very limited passholder quota on TGVs out of Brussels. It’s highly likely that there were never passholder seats on this train. Basically you can hardly ever book further than CDG Airport/Marne-la-Vallée due to the quota. The alternative could be to buy a domestic fare from Lille for example (more below though).

Second train: unavailable online. Only on the platform on the day, too risky in summer but...

This itinerary would work:

• TGV Bruxelles-Midi - Marne-la-Vallée (Disneyland) 10:17 - 12:08 20€
• same unit but new seat…
• TGV Marne-la-Vallée - Valence TGV 12:18 - 14:45 10€
• TGV Valence TGV - Barcelona-Sants 16:57 - 21:27 25€

However what you may (and should!) do: when the AVI arrives at 15:11 go and ask staff on the platform whether there’s availability...

• If there is: yay hop on and cancel the TGV booking (100% refundable until 30 min after departure)
• If there isn’t: too bad… 2 hours to keep busy in Valence TGV, maybe watching trains go through at 300 km/h

Feel free to ask anything. Book well in advance the TGVs (extremely popular route).

thank you very much for the answer, I think we will probably opt for your proposal, it is the most reasonable thing. Since I'm here, I'll also tell you that that day we are leaving from Amsterdam Central with an IC 9212 that goes to Brussels-Midi. In theory there is no compulsory reservation there, isn't there a risk of it being full?

Reservations are not possible at all on the IC so it will be fine. It might get busy at some point but since you’re boarding at the first stop you’ll have plenty of choice. :)

Btw if you’re fine with paying a bit extra you could leave later via Paris…

• Eurostar Paris-Nord 08:08 - 11:35 32€
• RER D Paris-Nord - Paris Gare de Lyon (pass not valid, get tickets onboard the Eurostar to save time)
• TGV Paris Gare de Lyon - Barcelona-Sants 14:42 - 21:27 35€

Unfortunately this route is expensive and choices are limited. Looking forward to the Amsterdam - Barcelona night train, hopefully from 2025!

I only now realize that the change in Marne-la-Vallée (Disneyland) is practically impossible😰

Why do you say that? It’s the same train (TGV9826). You might have to move from carriage 1 to 3 but that’s it. :)

I indeed mistakenly wrote 12:18 instead of 12:13 as the departure time but you’ll stay onboard regardless.

Btw if you book through Rail Europe you see seat numbers before payment so you could try to get seats near the previous ones!

I only now realize that the change in Marne-la-Vallée (Disneyland) is practically impossible😰

ah ok thanks so much again

I only now realize that the change in Marne-la-Vallée (Disneyland) is practically impossible😰

it is not possible to book in one go?

No, because of the stupid quota for TGVs out of Brussels (thanks SNCF...). You could board the TGV in Lille-Europe but it’s impossible to reach that station in time from Amsterdam...

I’ve suggested the best option I believe. It might be possible to get the exact same seats through Rail Europe if you’re lucky (there’s no seat selection unfortunately).