Situated at the mouth of a cave beneath a massive red sandstone cliff, the abbey of San Juan de la Peña benefits from one of the most dramatic locations of any medieval edifice. The monastery lies about thirty kilometres south of Jaca hidden within a rugged sierra which rises to a height of 1220 metres.
In the tenth and eleventh centuries it was the most important Aragonese monastery and although some way off the direct pilgrimage road and entailing a difficult journey, pilgrims would have been drawn there by its reputation as the major Cluniac centre of the region and the presence of the relics of San Indalecio.
Indalecio was considered one of Saint James’ original disciples during his ministry in Spain and had reputedly been ordained bishop by the Apostle himself, of the Roman town of Auca, 
the modern day Villafranca de Montes de Oca, itself a station further along the camino near Burgos.
After the Arab conquest many Christians fled from the Ebro valley up to the Aragonese mountains for safety. In 781 they were pursued by Abd-el-Rahman Ist who attacked and killed a group of Christians who had taken refuge at Monte Pano. Early in the ninth century a powerful Christan landowner from Jaca named Aznar Galíndez pursued a policy of encouraging Christian resettlement of the region on the southern side of the Aragon river. His son Galindo Aznárez II became the first count of Aragon, and he continued his father’s ressettlement policy.
During this period, two hermits from Saragossa, Voto and Felix established a hermitage at the foot of Mount Pano, where the red sandstone cliff concealed a large grotto which opened out onto a large entrance.
According to legend they found the body of another hermit Juan de Atarès and buried him by three altars which they had erected dedicated to Saint John the Baptist, Saint Julian and Santa Balissa. These were the patrons of a Visigothic monastery at Labasal in the Extxo valley which had been destroyed by Saracens suggesting that the hermits had come from there. They built a Mozarabic church.
The hermitage was known as San Juan del Monte Pano and developed into a monastery which began to play an important role in Aragonese ecclesiastical affairs, becoming the spearhead for the Cluniac expansion in the region.
King Sancho-Ramirez formed an alliance with the Cluniacs of the diocese of Auch just beyond the Pyrenees, which was aimed at bringing the fledgling kingdom of Aragon recognition and support from Rome and the rest of Christendom. In 1071 he invited the Cluniac monk Aquilino to become abbot of the monastery now renamed Jan Juan de la Peña. On Aquilino’s death the abbacy was taken over by the well travelled Sancho de Arinzana who had visited Rome, Monte Cassino and Compostela. Sancho de Arinzana brought with him the relics of two saints from Almeria, Indalecio and Jaime in 1078.
With these developments San Juan de la Peña expanded into a mighty abbey with substantial dependencies and lands, annexing some territory from the kingdom of Pamplona. The fortunes of the abbey and the political fortunes of the kingdom of Aragon became intertwined, as San Juan de la Peña acquired lands which were recovered from the Moors to the south during the conflicts of the Reconquista, thereby helping to define the territorial limits of the kingdom.
The construction of a new larger Romanesque church was begun with two funerary chapels, one for the laity and the other for the abbey’s monastic community. In 1083 the body of Ramiro 1st was transferred there and two years later the abbot Sancho de Arinzana was entombed.
Subsequently the new abbot Aimericus continued to acquire the older monasteries of the region and their dependent parishes so that San Juan de la Peña assisted by the favourable privileges granted by Rome developed into a veritable independent monastic state in its own right.
In 1094 the consecration ceremony for the new church was given by the bishop of Jaca in the presence of the king Pedro 1st and the countess Sancha and numerous important figures, including the archbishop of Bordeaux and the abbots of Leyre and Languedocian monastery of Saint Pons-de-Thomières.
The cloister of the abbey dates from around the middle of the twelfth century and the carved capitals are the work of a sculptor notable for his very distinctive stylistic traits. 
Unusually large bulbous eyes lend the figures an air of meditative grace which contrasts with the expressive attitudes of their bodies. The same original hand can be seen at work in several Romanesque sites in Aragon of the artist who has come to be identified as the Master of San Juan de la Peña.