Ruins of San Pedro de Eslonza Monument · Gradefes, Tierras de León, León The monastery of San Pedro de Eslonza, today reduced to ruins, stands beside the río de Eslonza, opposite Santa Olaja de Eslonza, in the municipality of Gradefes. It was founded in the year 912 by King García I of León under the patronage of Saint Eulalia and Saints Peter and Paul, and became the second most important monastery in the province, after that of San Benito de Sahagún. Destroyed by Almanzor in 988, it was rebuilt in 1099 by the infanta Urraca of Zamora, daughter of Ferdinand I. From 1547 the building was remodelled, fitted with three Renaissance doorways and a spacious cloister, and in the 18th century the grand Baroque façade was completed. The Mendizábal disentailment, in 1836, sold it at auction and hastened its ruin, which did not prevent its declaration as a Monumento Histórico-Artístico Nacional (National Historic-Artistic Monument, an earlier Spanish heritage designation) in 1931. Photo: David Perez (CC BY 3.0) What to see and do in Gradefes