I'm noticing this is a more difficult connection to make than I thought it would be! There are no direct trains from Marseilles to Madrid, so a night train is out of the question. Ryanair is the only airline that flies from Marseilles to Madrid, but their flight is rather late (9pm I think). We'll be there in October, and I have heard awful things about Ryanair canceling flights at the smallest weather problems. Would it be safer to ensure we would make it to Madrid to take a TGV back up to Paris and take an earlier flight on Vueling to Madrid from CDG, or even a train from Paris to Madrid? This would definitely increase the travel time, but we would arrive in Madrid in the afternoon rather than late at night, and we wouldn't have to fly on Ryanair. I think I wouldn't worry so much if the Ryanair flight wasn't so late; but if it was canceled, we'd be stuck for the night. Thanks for any thoughts!
Going to Paris seems counterintuitive, but I can see why you might do that.
Still I think you are wrong about "no night trains" from Marseilles. If you leave in the afternoon you can get a couchette once you change trains at the border.
It's a long haul, though, and I'd be tempted to fly.
Iberia flies that run....enter a fake return date and go for a round-trup fare. Mid-week in mid-August, evening flights, are around $195 U-S, all in...simply throw away the return portion.
Great idea about the R-T on Iberia! I couldn't figure out why a singly flight would be over $1000. I'll check into that. We've also thought about going to Lyon instead of Paris, which would be a shorter train ride; there are several flights out of Lyon. I'll have to check into that R-T trick. Thanks!