What is your travel date ?

Craiova - Arad : not available online but maybe at other countries ticket counters. Otherwise last-minute availability shouldn't be a problem (you may even be able to buy the reservation on-board but don't quote me on that)

Arad - Vienna + Vienna - Warsaw are doable on tickets.oebb.at : add Interrail/Eurail as a discount and select one-way tickets. Selecting seat reservations won't work (counter-intuitive I know).

- 3€ for a seat, 13€ for a couchette, more for sleepers

ÖBB doesn't show the correct timezone for Romania though : the 00:31 Arad departure is actually at 01:31.

So overall uncanny experince cos it’s as you pointed out “Selecting seat reservations won't work (counter-intuitive I know)” and also adding the pass into discount is kinda hidden in next extra steps.

Managed to pay but after payment process (it won’t charge actually when this error ir occuring) is done it’s either:

1:

So one must go again and again via all the options for seats - while there is no warning prior ordering, but the system know it, but won’t tell you untill one go through all the confirmations on phone for payment.

Or 2:

If I don’t specify that I would like only 2st class it order WITHOUT warning a 1st class reservation and it’s not even shown directly on confirmation - I discovered it by accident!

The first one is 2st class and second is 1st class.

This is done even when I specifically don’t choose 1st class option!

Thanks god my inner feeling push me to click that 3 min cancellation button severall times. Hope they return me money.

(In this case they charge cos payment is done in my banking interface.)

This is fuc*ed up in my opinion.

Not only that I spend quite few hrs trying to find out prior writing this post and thus loosing time and now there is no 2st class reservation possible but also all the process is bit fradulent (ordering 1st class while I don’t have a ticket for that without asking me) and not intuitive (there are no seats available yet it let me go all the way throught reservations while it’s absolutelly unnecessary).

Well I gave up on this, never again.

Last question, is it possible to board train without reservation?

I will roam from seat to seat if someone with reservation shows up. Or just stay in aisle in worst case scenario.

Thx for info on this.

The train Vienna-Warsaw may be almost full in 2nd class on 2 June. Nevertheless, I can still get to the payment page (to enter my card details) for a 2nd class seat using "Seat reservation only”.

You can enter the train without a reservation but it is mandatory to have one from Bohumin.

I can still get to the payment page (to enter my card details) for a 2nd class seat using "Seat reservation only”.

Yes, that is what I'm talking about in post above. Reservation system let you in - it will create reservations and let you pay only to return error or create reservation even for 1st class while not notifying one about that.

I tied CZ Můj Vlak app - it shows this:

(At least the app won't lie about availability and won't allow buying a ticket, it forcing you for 1st class the way you notice it.)

What is the "intended for passengers without seat reservations"?

Like they put me here and I will pay some fine? 

Or they will throw me out of the train?

Only reason why I would like to have a reservation is the possibility of seat without roaming around.

But I don't have a problem with that in general - I'm commuting by train for 20 yrs or so and just stay in aisle in case there is no space.

The way I understood the concept is it's only an option for more comfortable trip.

Mandatory reservations are a new thing to me cos I never imagined a possibility that it's not allowed for one to stay "out of seat".

I just don't get it at all.

This totally ruining my trip.