travel in Northern Spain

Just remember there are days to travel and days to see things. You can make daystops on a travel day as long as you aren't planning long travel legs or a stop that requires more than a few hours. Each full day at a destination requires staying 2 nights, 2 days = 3 nights, etc. Three days is pretty good for Barcelona, there is a lot to see.

ViaMichelin says about 5 1/2 hours drive to Pamplona, I'd plan that as a minimum. On a travel day, you have to get up, get ready, pack, check out, get to your transportation (train, car rental), wait for your transportation, make connections (if you're on a train), get off at your destination, get to lodging, check in and get settled. Somewhere in there you're going to want meals. I normally try to plan 4 hour legs on travel days to avoid that "death march" feeling. I also try to plan mostly multiple night stays for the same reason. We had three stops between the Barcelona and Pamplona, Montserrat, Zaragosa, and Olite - so took it in shorter hops. Each is a nice stop. Depending on your personal interests, one may be a must see while the others are skippable. I'd rate the castle experience in Olite right up there with many I've visited around Europe. Although it's relatively small, you can wander at will and the audio guide gives you a good impression (in a variety of languages) of how it would have looked when the King of Navarre lived there.

Donastia (San Sebastian) is nice. It's a place you could stop and relax or just enjoy a look around and some seafood before moving on. From there you have a ton of options, but not enough time to experience them. Via Michelin takes you through Vitoria and Burgos which I think is a good choice. Vitoria is the center of the Rioja wine region. If you plan ahead you can look around the old center and reserve a Bodega tour (Bodegas here don't do drop in tours). I'm not a fan of Madrid except the Prado (plus maybe Temple Debod) there isn't much there that interests me.

Death march aside. If I were trying to do your route. I'd spend three days in Barcelona. On day of arrival, I'd walk the Ramblas and up the beaches, maybe throwing in a couple interesting sights. On day two, I'd see the Gothic Quarter and nearby sights that interest you most. Day three would be for Modernist architecture. Day four, pick up a car around 6 am. Hopefully you pack light. If not, get a big car - because they don't have giant trunks. I'd stop at Montserrat on the way to Olite. If you spend time hiking there, plan to arrive in Olite in time to check in and eat dinner. If you only take a quick look at the monastary, try to get to Olite before the castle closes and see that. Day five, see the castle first thing (if not before), look around Pamplona for an hour or two, then stay in Donostia (time on the beach if you get there soon enough). Day 6, head to Burgos with a stop in Vitoria (hopefully you booked a Bodega tour ahead). The center in Vitoria is small and worth a quick look around. Burgos has a lot to offer. Ideally, you have the afternoon to look around then spend the night. Day 7, into Madrid. That gives you the time you wanted in Madrid. Alternatively, slice a day off Madrid and spend more time on the coast in either Donostia or, just into France, at St. Jean de la Luz.

Brad-
Thank you for your thoughtful and meaningful suggestions. Wish us luck! Ron