Driving from Zaragoza to Toulouse?

Can't help with driving times. Have you looked at ViaMichelin?

Zaragoza, Vitoria-Gasteiz and Burgos are all worthwhile. Zaragoza could be 15 or 20 degrees (F) hotter in mid-summer, though.

I really enjoyed a day-trip (round-trip) on the SNCF Yellow Tain last year. The route is through the Pyrenees from Villefranche-de-Conflent (Villefranche-Vernet on the schedule) to Latour de Carol. Three of the five trains per day stop at Font-Romeu Odeillo Via rather than going all the way to Latour de Carol. Both Villefranche and Mont-Louis are fortified towns. Villefranche seemed very touristy last year. I think Mont-Louis probably isn't so bad, but it's a good little walk from the nearest Yellow Train station. I saw no signs, so one would have to navigate with an electonic map or by instinct.

I would suggest going from Donostia to Jaca. I would avoid Zaragoza in the summer. Hot. (The same can be said about Burgos) Also Jaca is on the E07 route, and it would cut about an hour and a half of travel time to Toulouse.
Jaca is a nice little city and there are various sights in the area. There is the monastery of San Juan de la Pena, which is supposed to be one of the resting places of the Holy Grail. Near by is the Loarre Castle, where Ridley Scott filmed part of Kingdom of Heaven, and the Castle of Javier, birthplace of St. Francis Xavier.

Day
1. San Sebastián to Zaragoza, visiting Pamplona on the way
2. Explore Zaragoza
3. Zaragoza to Toulouse, visiting Cirque de Gavarnie on the way
http://ete.gavarnie.com

Thanks all for your thoughts!

Anyone think Vitoria Gasteiz worth 2 nights? Or better to stay in San Sebastian and do day trips around?

Cheers,
C.

That's a tough question. I think if you timed your arrival and departure so that you basically had just the one full day, you could probably fill the time if you're interested in the art museums. There's also a playing-card museum. Or you could walk every street in the historic district as I like to do. I do recommend the tour of the cathedral if they're still offering it in English.

I'm still writing up my trip report for the Basque country in May 2017, but here's a preview. I had one night in Vitoria, and saw:

a) Some of the archeology museum (free). Only some, because descriptions are in Basque and Castilian only, and, while there is a free English audioguide if you know to ask for it, only a few items had audio descriptions.
b) The playing card museum, in the same building as the archeology museum (free). Very interesting if you are into this sort of thing. Don't miss the Kamasutra deck, or the one owned by the Sforza-Visconti family made of parchment with gold leaf. Here, the audioguide covers each room - very helpful.
c) The Museo de Bellas Artes, or Fine Arts Museum (free). This is fantastic - I rarely call anything a must see, but if I ever did it would be this. Not only was it filled with my favorite kind of art - great stuff that I've never seen before, by artists I've never heard of, so it's all a surprise - but it had only a few other visitors, so I could enjoy everything in solitude.
d) The Artium, or modern art museum (€5). This had four exhibits, three of which I liked and one of which I found only OK. However, I still felt visiting was worthwhile (although an inevitable comedown after the Fine Arts Museum). In addition it has longer hours than the other museums (the reason, with only one day, that I saw it last).

Note that all of Vitoria's museums (the town's tourist brochure lists 7) are closed on weekdays from 2 to 4 PM. All but the Artium reopen from 4 to 6:30; the Artium reopens from 5 to 8. I do see from their website that the Artium has no midday closing on Saturdays and Sundays, but some others are open shorter hours (morning only) to compensate. In addition, all seven museums are closed on Mondays.

The upper old town of Vitoria may be pretty, but it was pouring rain when I was there so I wouldn't know. Fortunately it had stopped raining when I saw some of the lower town (the commercial center), which has some pretty areas as well.

If you're looking for a hotel in Vitoria, I recommend the Desiderio (http://hoteldesiderio.es/ - use Google Translate if needed). It's a block from the Artium (and its taxi stand, very handy for getting back to the bus station) and 5 minutes from the Bibat, which is the combined museums of archeology and playing cards. My single room was a steal at €35 per night.

SO, if you're as interested in the museums of Vitoria as I was, two nights would be very good, so you won't rush around as much as I did. If you're not as interested, or if you're there on a Monday when they're closed, one night is probably enough.

While Zaragoza is nice and I really enjoyed it, I'm not certain driving all the way there is the best use of you time. Acraven had some good alternatives. Also, you say the drive is on the E07, but that's only after you get out of the Pyrenees. The road through the mountains is the N330 which is going to be a good road but not an interstate. Spain's N (nacional) roads are 2-lanes; one each direction. They will twist and turn going through the mountains and go through every small town. They are well maintained but expect that part of the drive to take longer than the interstate portion.