San Salvador de Valdediós stands in the Boides valley (Villaviciosa), the place where Alfonso III was detained when he was dispossessed by his sons, and where there used to be an old convent governed by the Benedictine Order, substituted in the 13th century by the Cistercians. The church known as the "Bishops' Chapel" was consecrated on September 16, 893, with seven bishops in attendance, and stands on a classic basilica ground plan with a triple sanctuary, separating the central nave from the side aisles with four semicircular arches. At the western end, there are three enclosures, the central one used as an access vestibule, and two located on the left and right which may have been used to house pilgrims. The vault over the central nave, like the one over the apses, is barrelled with a brick ceiling and decorated with al fresco wall painting, alternating a variety of geometric designs. The royal tribune is located above the vestibule, separate from the area intended for the congregation (spatium fidelium) in the central nave, and this from the area devoted to the liturgy by iron grilles, now disappeared. Particular elements of this church include the covered gallery annexed to the southern facade at a later date or Royal Portico, the 50 cm square columns on the central naves arches, the triple-arched window open in the central apse, and the room above it, exclusively accessed from the exterior by a window which here has two openings, compared with the habitual three. The Church of Santo Adriano de Tuñón is located on the bank of the River Trubia, next to an old Roman road. Founded on January 24, 891, it stands on a classic basilica ground plan, although in the 17th and 18th centuries it was extended with a nave structure at the western end, and a bell gable. The al fresco paintings in this church are the only remains of Mozarabic painters' work in an Asturian art workshop. Finally, the Foncalada fountain, the only upper medieval civil construction conserved in Spain, was built on the outside of Oviedo city walls, with stone blocks and an intersecting roof, barrel vault and rectangular ground plan. The intersection of the roof is topped with a triangular pediment, sculpted with the Victory Cross, characteristic of Alfonso III, under which runs the typical inscription of the kingdom of Asturias: Fifth period (910 to 925) With Alfonso III