The church of Saint Mary at Mount Naranco (Spanish: Iglesia de Santa María del Naranco; Asturian: Ilesia de Santa María'l Narancu) is a pre-Romanesque Asturian building on the slope of Mount Naranco situated 3 kilometres (1.9 mi) from Oviedo, northern Spain.Ramiro I of Asturias ordered it to be built as a royal palace, part of a larger complex that also incorporated the nearby church of San Miguel de Lillo, 100 meters away. The palace was completed in 842 and had in part a religious function, being consecrated in 848. Its structural features, such as the barrel vault—with transverse ribs corresponding one-to-one with contraforts at the exterior, make it a clear precursor of the Romanesque construction. The exterior decorations, as well as the use of stilted arches, mark the intended verticality of the composition.
It was declared a Monumento Nacional on 24 January 1885. Along with all other national monuments of Spain, it was classified as a Bien de Interés Cultural in June 1985. It was declared a World Heritage Site by UNESCO in December 1985.