Complex sentence: But the most representative monument in Naron is the Romanesque Church of O Couto, in the ancient monastery of San Martin de Xebio, from the 12th-century, which has basilical layout (three naves and semicircular apses).
Split into simpler sentences: But the most representative monument in Naron is the Romanesque Church of O Couto, which is in the ancient monastery of San Martin de Xebio and dates from the 12th-century. The church has basilical layout (three naves and semicircular apses).