It's inner walls were richly decorated with paintings that pushed one step beyond the geometrical decorations of San Julián.
But probably due to its location -too near of a stream- and the instability of the ground on which it stands the proud construction collapsed down in the XIIIth century to a third of what it had been. A new apse was made to keep it going.
The original layout of the church is marked on the outside by a line made of pieces of wood.