The Cross of Charlemagne marked the first station of the Spanish pilgrimage road to Compostela. The Cize mountain over which pilgrims passed was believed to be the highest mountain in the whole of the Pyrenees. According to the Pilgrim’s Guide, from the summit one could see as far as the Atlantic ocean.
The Guide tells us that on the summit there was a cross which had been placed there by Charlemagne when he entered Spain on his way to liberate the shrine of Saint James at Compostela. 
A papal bull of Paschal II in 1106 decreed that this cross designated the boundary between the dioceses of Bayonne and Navarre, thereby making it a de facto marker between French and Spanish territory.
The custom grew that pilgrims having made the ascent would erect their own crosses so that, as the Guide puts it, “one can find there up to a thousand crosses”, affirming that it was the first station of prayer on the road to Santiago de Compostela.
The Cross of Charlemagne was one of a number of sites on the pilgrimage road associated with the legend of Charlemagne’s Spanish expedition and which are indicated in the Pilgrim’s Guide.
On the northern slopes of the mountains was Valcarlos “where Charlemagne encamped with his armies” while the battle was raging in the heights above at Roncevaux.
Immediately beyond the Cize Pass there was a hospice and a church built over the very rock “that Roland, the great hero, split with his sword in the middle from top to bottom with three strikes of his sword.”
Just below this pilgrims reached Roncevaux itself, “the place where for sure, the great battle took place in which were slain King Marsile, Roland and Olivier and others together with forty thousand Christians and Saracens”.
It was a part of the intention of the Pilgrim’s Guide to direct pilgrims towards the reliquary sites that were considered essential on the road to Compostela.
Among the list of the tombs of saints advocated by the Pilgrims Guide were those of the fallen heroes of Roncevaux. “Next to Blaye on the seashore one must ask for the protection of the Blessed Romanus in whose basilica” the Guide informs us, “the remains of the Blesses Roland the martyr rest”. We are told that the Olifant was held at the abbey of Saint Seurin at Bordeaux.
A paragraph in the Guide is dedicated to providing a list of those paladins martyred at Roncevaux who were buried near the town of Belin. Among these was Roland’s companion, Olivier.
The passage of Charlemagne’s armies in Spain is again evoked when the Guide describes the Cluniac abbey of Sahagún in Castile. Pilgrims were directed to visit the remains of its saints, Facundus and Primitivo, and that their tombs were contained in a church built by Charlemagne. 
“Next to their town,” the Guide continued, “there are wooded fields where it is related, the lances of the warriors which were planted in the ground, grew leaves again”. This was a reference to the miracle of the lances recounted in Turpin’s History.
The great events of the historic past which themselves were reiterations of sacred events from the Biblical past were authenticated by these hallowed places that pilgrims visited on their way to Compostela. Visible and tangible evidence directly linked to the goal of their journey and the legendary material which surrounded it, was an integral part of medieval pilgrimage.
Biblio: Bernard Gicquel La Légende de Compostelle Le Livre de Saint Jacques, Tallandier 2003, The Pilgrims’ Guide to Compostela, Melczer, Italica Press New York 1993, The Interaction of Life and Literature in the peregrinaciones ad loca sancta and the Chansons de Geste, SG Nichols Speculum 44 1969 51-77