This church has been declared an “Asset of Cultural Interest”. This temple preserves Romanesque remains in the main chapel, as well as in its corbels. Most of the construction belongs to the Gothic period, which from the beginning of the fourteenth century was built in several stages.
At the beginning of the eighteenth century, the chapel of Socorro and that of Carmen were added. When the French sacked the town, a fire destroyed the entire interior of the church. Throughout the nineteenth century, the bell tower was affected on three occasions by various lightning strikes; of these, the most serious occurred in 1885, coinciding with the feast of San José, which caused three deaths and more than 60 wounded. In addition to the tower, it affected the façade and the roof. There are several different versions of the origin of San Marcos de A Cadeira, which is preserved inside.
The church is organized in a rectangular hall plan, with a single nave, and a rectangular main chapel. The nave is divided into four sections by three pointed arches with edges. The arches rest on semi-columns, topped with capitals decorated with schematically carved leaves. The nave has a gabled wooden roof. The Main Chapel is covered with a cupuliform vault (of Byzantine influence) that goes on diagonal ribs turned on elbowed columns.
