Holy Chamber of Oviedo

The Holy chamber of Oviedo is a Roman Catholic pre-Romanesque church in Oviedo, Spain, built next to pre-romanesque Tower of San Miguel of the city's cathedral. Nowadays, the church occupies the angle between the south arm of the cathedral transept and a side of the cloister.

It was built during the 9th century as a palace chapel for King Alfonso II of Asturias and the church of San Salvador of Oviedo. Apart from acting as royal chapel, the Holy Chamber was built to house the jewels and relics of the cathedral of San Salvador in Oviedo, a function it continues to have 1200 years later. Some of these jewels were donated by the Kings Alfonso II and Alfonso III, and represent extraordinary gold artifacts of Asturian Pre-Romanesque, brought from Toledo after the fall of the Visigothic kingdom.

Source: Wikipedia