I’ll add to all the other comments good explainations that as trains use tracks, it all depends on where are all the other trains and when. So fast trains (at

I’ll add to all the other comments good explainations that as trains use tracks, it all depends on where are all the other trains and when. So fast trains (at least in France that you should have cross to go to Barcelona) must have very specific time tables and get along with local trains, when airplanes don’t and can go straight. It adds constraint. (Ok, I know planes have routes too, but it’s much easyier to do timetables)