Train switch in Brussels Belgium

Provided the Thalys train arrives on time, 13 minutes is more than enough time. Brussel Zuid has a standard track layout. All the platforms run parallel to each other and you move from one to the other by an under track walkway. Finding your connecting track will be a simple matter of going down one set of stairs, turning left or right, a short walk, then up another set of stairs to your platform. "Also, I have been told to reserve 2 seats on the Thalys train several weeks ahead." To take advantage of advanced purchase discounts, yes. Otherwise, if you don't mind paying full price, you can buy your tickets just beforehand.

I should have said that we have Eurail Global passes. So I understand that some trains have limited availability and require a reservation - including the busy Thalys trains. Thank you very much. John

John, although it's too late to snag the cheapest Thalys fares, you may still get a better deal on a regular discount ticket vs the very expensive Passholder fare. Do check into that. For a Midi map: http://www.b-rail.be/nat/E/assets/downloads/brux_midi_angl.pdf My experience, and this map, tell me that (usually, anyway) your TGV train should be close to the Thalys tracks...But check the boards ASAP after you leave the Thalys train to confirm this. Don't plan using any of the station's services (toilets, snack bars, etc.), because you won't have time. Picking a Sunday in Sept, I can't find your particular train, and I don't know your travel date, so this is as close as I can get...

Yes, as said above, it should be doable. In addition to the stairs mentioned there are also escalators. That being said, if it were me, I'd get to Brussels earlier. I'd have a bite to eat, a browse for choccies, a visit to the toilets, visit the supermarket for supplies for the onward trip, and find with plenty of time where the TGV car that you need will be. These are all available in Brussel Zuid/Midi. Many TGVs from Brussels to the South of France are two trains coupled together, without through passage from one to the other, and it is important that you are in the car you reserved. In addition to the problems mentioned above for pass holders on Thalys - so difficult that you are often better ignoring the pass and going for a cheap normal ticket; there can be similar problems using passes on the TGVs. TGV rations pass-holder tickets so if you don't get your reservation early you may not be able to travel on the TGV you want.

Personal preference - it's already a nighttime arrival; I'd want to arrive at my destination ASAP. I also buy my trip goodies (food, water, snacks, wine/beer) the day before. I've already had a very bad experience with an all-day, fancy-schmancy TGV train that didn't have a single bottle of water for sale (the cafe car dude dudn't show up...). And lines at train stations can be long (snack bars, toilets). Go potty on the train! That's a huge station...when you probably won't need to go far to change tracks, I personally would limit my steps. But that's just me ;-) But if you want a longer transfer time at the station, it looks like you'll need to move your second leg out; you're already on the first train of the day (again, not knowing the exact date of travel, but...).

Thank you all very much, I am rethinking. Might have to leave Amsterdam earlier or take the later TGV. We are going to Arles and I did not want to get in too late. Thanks again and again.
John