Bayonne to Madrid - need 2 night stopover

I think 2 nights in Zaragoza would work well. I think there is a direct train from Bilbao to Zaragoza, you could also take the ALSA (high end long distance) bus from Bilbao to Zaragoza. Both options take about 4 hours. From Zaragoza, you can take the AVE high speed train to Madrid in like 1:30 hr.

Zaragoza has more than 2,000 years of history including Roman ruins of the city walls, forum, and amphitheater. Also don't miss la Aljafería an 11th-century Moorish palace, the most northern Islamic palace in Europe. Throughout Zaragoza you'll find Mudéjar architecture, a unique mix between Moorish and Christian styles and motifs, designated a UNESCO world heritage site. Zaragoza is also the home to the Nuestra Señora del Pilar Basilica, which has one of the best church exteriors in all Spain imo. Zaragoza is unique as it's virtually undiscovered by foreign tourism.

Thanks so much

I’ll second Carlos’s recommendation, and add just a couple of points. There are many Art Nouveau buildings in the pedestrianized center, which makes that area very pleasant for just meandering. Also, there is, of all things, an origami museum. It’s not really close to the other attractions, so you wouldn’t just come across it unless you were looking for it. Very interesting.

Really liked our 3 nights in Zaragoza.
The Origami Museum is great.
https://en.wikipedia.org/wiki/Aljafería Is a must see.

Thanks so much for your thoughts about Zaragoza. However, I have been following the flooding in Zaragoza, July 8 and looking for follow-up information. Would Segovia or Burgos be better 2 night choices between Bilbao and Madrid? Thanks again.

Burgos is larger. I love its cathedral with the tomb of El Cid and his wife Jimena. There is enough to do to occupy two nights. Just outside the city is the 1400s palace turned monastery, Cartuja de Miraflores. It can be walked to from the center city (2.5 miles). I like Segovia too. It’s much smaller and the major draws are the Alcázar and the Roman aqueduct. Segovia probably draws in more tourists. In Burgos you’d get to see pilgrims walking the Camino de Santiago. Burgos is between Bilbao and Madrid, while Segovia is slightly west. I guess I’d stay in whichever is easier to get to.

The last time we were in Burgos we stayed at Abba Burgos Hotel and enjoyed it and its location.

Edited: I looked at video of the flooding in Zaragoza and while the river rose, it didn’t rise enough to flood the basilica, the plaza in front of it, or the town itself. Towns south of Zaragoza weren’t as lucky.

I second Jaime's praise of Burgos. The cathedral is impressive and the Cartuja is was a real surpise for me. There is a lot of history in the city. If you are not that interested in kings and history, you can also go to the excavations at Atapuerca and learn about cavemen and neanderthals.