St Jean in the distance below.

The inscription on the shell reads "Sur les chemins de St-Jacques de Compostella" (On the road to St Jacques de Compostella).
The text above that is in French, and a loose translation reads:

"The Guide Pelerin (12th century), attributed to Aimery Picaud, cites three steps leading up to the Pyrenees on the way to Saint-Jacques de Compostela ... The author of the Guide describes the passage of the Pyrenees:

"In the Basque country, the road to Saint-Jacques crosses a remarkable mountain called Port Cize ... to cross it, there is eight miles up and down across a mountain so high that that in going up it the pilgrim could believe that his own hand might touch the sky"