The Mother Church of Barcelos, dedicated to Santa Maria Maior, is a monument that maintains its medieval robustness in appearance, embellished by decorative and architectural elements that reveal the imposition of the Gothic style on a Romanesque structure. Its construction began in the second half of the 14th century on the initiative of D. Pedro, 3rd Count of Barcelos, whose weapons are engraved on the archivolts of the main portal.

Inside, the historic Romanesque capitals affirm the medieval atmosphere, contrasting with the tile panels from 1721, which present scenes from the life of Our Lady. In the various side chapels, the baroque decoration stands out, in particular the gilded altars. In the main chapel, there are some mannerist paintings representing the Annunciation and the Adoration of the Shepherds. The church is one of the greatest exponents of Romanesque architecture in the north of the country and underwent major transformations throughout the 15th to 18th centuries. In the 20th century, the rose window was restored, and on the south side of the facade there is a bell tower dating from the 18th century. It has been classified as a National Monument since 1927.