Between here and Pamplona, you will notice many villages perched above the valley floor. This was to maximize both farmland (shared and more fertile near the river) and security.
The last Sunday in August.
The founding of Espinal was driven by the desire to protect pilgrims. This river valley has a long history of battle and banditry, and it was in the interest of the Navarran Kings (in this case Teobaldo-II) to keep them safe.
Several more villages along the way share a similar founding, and Teobaldo was not alone in improving the infrastructure of the camino. Indeed, several other Kings, Queens, Saints, and modern politicians all share a common interest in promoting the camino.