Northern Spain -- Bilbao to Barcelona Seeking Input on Itinerary

Are you staying in Logrono or Laguardia? We enjoyed the wine towns and wine tasting.
The San Telmo Museum is excellent. You may find yourself short on time in San Sebastian.
We really enjoyed the half day or so we spent in Vitoria-Gasteiz. We picked up an excellent sightseeing/walking tour map at the TI.
If you are taking a day trip while you are in Girona, you don't have enough time there. Lots to do in Girona including walking the city walls. Girona is one of my favorite places in Europe. (you have 2 nights in Girona which means you only have one day)

I feel Laguardia can be adequately seen in a few hours. Others will disagree. If planning to visit Church of Santa María de los Reyes, check its open hours. In Laguardia, park in the free lot near the PISCINAS MUNICIPALES and take the elevator (Ascensor de Laguardia) to the historic center. I’d stay in Logroño another night before spending a night in Laguardia. Laguardia is only 10 miles from Logroño. A couple other towns meriting short stops near Laguardia are San Vicente de la Sonsierra and Briones.

Between Logroño and Pamplona, Puente de la Reina and Estella are worth walking around. A couple short stops en route could include Church of Saint Mary of Eunate and Alto de Perdón.

While Pamplona is worth visiting, Olite is worth a night or two because of its Royal Palace. I will say the bullring tour in Pamplona was nice and you get to see some things other bullring tours don’t include. Pamplona does have more restaurants than Olite. There are no wow sites in Pamplona.

It’s a shame you don’t have more time between Pamplona and Girona since there’s so much to see between those places. On the day you visit San Juan de la Peña monastery, if you had the time, take the detour over to Loarre Castle before continuing on your journey.

When I was planning my similar trip, we dropped Pamplona because people on the forum seemed a little lukewarm about their visit to Pamplona. You might ask for feedback on Pamplona vs. other possible sites.

Between Pamplona and Girona is the entire region of Aragon, an underrated gem, which you seem to be entirely skipping past. In my opinion this is a mistake, this region has arguably everything you are looking for and more, with a car it is all accessible to you

Allow me to start by describing Zaragoza, the regional Capital of Aragon. Located in the shadow of the Pyrenees, Zaragoza was once the seat of the mighty Kingdom of Aragon, whose possessions included southern France, Sicily, and even Greece during the middle ages. If you like history and art I can think of no other city in Spain than Zaragoza that encapsulates almost every facet of Spanish history and art. More than 2,000 years of history in fact, including Roman ruins of the city walls, forum, and amphitheater, and the 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. Zaragoza is also the home to the Nuestra Señora del Pilar Basilica, which has one of the best church exteriors in Spain.

I think that Zaragoza is one of those undiscovered gems that Rick Steves calls "back doors". It reminds me a lot of Barcelona before international mass tourism really took off. The best area for tapas in Zaragoza is a neighborhood called El Tubo (https://www.spain.info/es/lugares-interes/barrio-el-tubo/). Another good place to eat is a Gourmet Food Market off the Plaza de España, called Puerta Cinegia Mercado. The historic Mercado Central de Zaragoza, with its wrought iron exterior, has recently been renovated and is a delight to explore.

From Zaragoza there are many day trip you can go with a car:

Tarazona - medieval town where Muslims, Christians and Jews all lived in harmony. The town's unique architectural eye candy reflects this synergy between the three cultures. Tarazona’s medieval Jewish Quarter is the best preserved in the region.

Olite - a fortified medieval town with winding narrow streets and impressive old walls. Don't miss the Royal Palace of Olite, the seat of the Kings of Navarre, actually incorporated into the old town's fortifications. For me, it's one of the more impressive medieval castles in Europe.

Castillo de Loarre - one of the oldest castles still standing castles in Spain, it was featured in Ridley Scott's epic film Kingdom of Heaven. The location of Loarre Castle is very picturesque as it sits high on a cliff overlooking the southern foothills of the Pyrenees.

The Ruins of Belchite - During the Spanish Civil War, Spanish Republican and General Franco's forces fought the Battle of Belchite in and around this town. After 1939 a new village of Belchite was built adjacent to the ruins of the old, which remain a ghost town as a memorial to the war, which can still be visited with a local guide today. You can read more here - https://www.atlasobscura.com/places/the-ruins-of-belchite-belchite-spain

Trasmoz- The only town in the world to be excommunicated by the Pope. Tucked in the foothills of the haunted Moncayo mountain range, Trasmoz has centuries of witchcraft history. You can read more here - http://www.bbc.com/travel/story/20160418-spains-cursed-village-of-witches

Ordesa y Monte Perdido National Park - One of Spain's oldest national parks and a UNESCO World Heritage Site. Located deep in the Pyrenees Mountains, imagine towering peaks, deep green valleys, and beautiful waterfalls, There are tons of trails, whether you want an easy walk or a challenging hike. Late summer will be a good time to visit.

For my money I'd drop everything between San Sebastian and Girona, and reinvest those nights in Aragon, using Zaragoza as a base to explore the region.

Agree wholeheartedly with Carlos and Jaime(The Wise), Aragon is full of under the radar treasures. We spent 3 nites in Olite..wonderful. The Pyrenees are spectacular... charming mountain villages... drop dead scenery.

Brad

But Olite is in Navarra, not in Aragon...

Be sure to see the Peine del Viento at La Concha. It is great fun! Also, highly recommend Chillida Leku, outdoor museum of Eduardo Chillida’s work, nearby to San Sebastian.

In Aragon, I really enjoyed Sos de los Reyes Catolico. It is where Ferdinand of Aragon was born but what I loved was that it was a totally medieval looking town. So many 'old towns' are surrounded by new town sprawl. Not Sos. Incredible. There is a nice parador there.

In Logrono, head to Calle Laurel for the tapas.