Now we're talking! I suggest you drive towards the French border town of St.Jean pied-de Port and stop along the towns that have grown up along the Camino de Santiago.
Here are some suggestions:
Valcarlos (the city may not look like much, but if you go north off the main road right across the street from City Hall, and go up the hill to the left, you'll happen upon an old Basque cemetery with some older, whitewashed headstones). This is the first all-Spanish town along the Camino.
Roncesvalles: A bit more well-touristed, there is much to see and much history, including a nice little museum with some old relics and artifacts.
Burguete and Mezkiritz: Two very typical Basque towns; small and quaint.
There are a number of other small villages along the road, many with hidden treasures.
Getting off the road and into Gipuzkoa, I recommend Azpeitia or Andoain. Azpeitia is nice and nestled into the green hillsides of the area.
West of Pamplona, you will find Puente la Reina/Gares along the Camino. Great little place, and loads of history. This is where the eastern roads to Santiago converge into one.
Further west are the cities of Estella and Navarrete, both worthy of your time, and the Monastery of Iratxe, which is also worth the trip.
Too bad it's Semana Santa and not Mes Santo, you'd have more time to visit all these places!!