Sorry, just one more: in my opinion(sorry, Maribel), St Jean de Luz, Biarritz and Bayonne can be done in one day. It takes half an hour from SS to get to St Jean de Luz, then another 20 minutes to BAyonne and about 40 minutes to Bayonne, on the highway. You can take the coastal road (full of roundabouts) and enjoy the views. To the west of SS Getaria, Zarautz and Lekeitio are a must, if you have time.

Hi mikel and sgp,
I need to confess that the reason I can't do St-Jean-de-Luz, Biarritz and Bayonne on the same day is that I'm a shopper!!

I love the French Basque linens and tableware (and ceramics) of Helena, Euskal Lingue Basque and Jean Vier (my home is filled with them), so it takes me a while to look at the new styles and replenish my towel, tablecloth and placemat supply, and the shops in StJdeL and Biarritz have slightly different inventories. We also take "orders" from friends in the US.

I also like to spend a good couple of hours at the Tues./Fri. outdoor market in St-Jean-de-Luz because it's just one of the very best in the Pays Basque.

The top purveyors of hams, brebis cheeses, pâté, honey, black cherry confiture, gâteau basque all come to you-you don't have to go to their farms (although we do that too). While farmers' markets in my home city are ok, they just can't compare with those of SW France, I'm afraid!
And we take orders from US friends here too.

Third reason is that we always spend at least a couple of hours at the fascinating Musée Basque (ethnography museum) in Bayonne and buy a combined ticket for it and the fine arts museum next door, the Musée Bonnat.

But for those who don't want to shop or spend an afternoon on the very family friendly beach of St J de L or visit the Musée de la Mer or Asiatica Musée d'Art Oriental plus churches in Biarritz or tour those two fine Bayonne museums, you can get a "look" in one day.

I just like to split them up and savor, but I have the luxury of ample time to do so.
And we have to visit in high season when the N 111 is jam packed and very slow going.

sgp,
The waits for the train to La Rhune, the Basque "sacred mountain" during high season can be more than 2 hours long, if you don't arrive to line up by 8:30 am. This is an extremely popular family outing among the locals. Lots of family groups, both French and Spanish. In July/Aug. most people want to take the train early then do the 2 1/2 walk down before it gets too hot (my friends scold me for not walking BOTH ways).
It's a 35 min. ride one way. But don't plan on it if it's a cloudy day. Read all about it here-
www.larhune.com

correction-the coastal route, through St-Jean-de-Luz, Guéthary, Bidart, Biarritz is the N 10, usually bumper to bumper in mid to late July and Aug.

Right, on those months I´d take the highway, because the traffic is really, really slow on the N10.