Inside the Sanctuary of Our Lady of O Corpiño, it is clearly revealed the older building. The remains can be seen in the lower part of the temple and are made in granite ashlar. The reform of 19th century regularized the cut of the stones. It gives a more homogeneous and aesthetic appearance in the transept and in the access to the side chapels. The central nave is covered by a barrel vault and is marked with arches. The crossing is covered by a dome on pendentives with a lantern.
The presbytery is covered by a beautiful groin vault ornated with beautiful mural paintings of vegetables in scrolls. It is divided into four parts, framing different anagrams and scriptural symbols: the anagram of the Virgin Mary (the M and the A intertwined), the Lamb lying on the book with the Seven Seals, the Dove that represents the Holy Spirit and the Tablets of the Law given by God to Moses.
The side naves are covered by impressive flat roof formed by colossal ashlars stone. This are supported by slender pilasters.