I'm taking the RS Loire/So. France tour at the end of June. I arrive on a Saturday in Paris. I leave Sunday morning, to go to where the tour starts in Chartres. My question is: do I have to buy tickets ahead of time from Gare Montparnesse to Chartres or can I just show up at the station that day? Is it more like a commuter train where I can just purchase at the point of departure, since it's only a 1 hour ride?
Also, I would prefer the direct train, rather than making one stop. Does this make a difference?
I need to validate, correct.
Even though I have been on trains before, I've never done it in Europe, so thanks for the advice.