The Church of San Xés de Francelos, declared a Historic-Artistic Monument in 1951 and a Cultural Heritage Site in 1985, is built from the remains of a much larger Monastery. It is believed that the current temple corresponds to the apse and its famous Visigothic horseshoe arch would act as the entrance to the main chapel. The temple is a rectangular body of small dimensions, with canonical orientation and a gabled roof. Nevertheless, this monument showcases various architectural styles that make it an almost unique church. In addition to the mentioned Visigothic horseshoe arch, we must add the Mozarabic arches and the engravings and stone latticework found on its façade, works of great sculptors, and the vegetal decoration. The columns and shafts we find correspond to late Romanesque art. All of this blends in a temple with characteristics similar to the Church of Santa Cristina de Pola de Lena; of Asturian-Romanesque style. Thus, we are faced with a temple that presents examples of up to four different architectural styles: late Romanesque, Visigothic, Mozarabic, and Asturian pre-Romanesque. For this reason, it is extremely complex to make a precise chronological dating. There are references to it in the Tumbo of Celanova as early as the year 993, so it is believed that its construction dates back to around the 8th and 9th centuries. In 1985, there is evidence of the existence of a large necropolis located under the chapel floor that dates back to the early Middle Ages.