Some elements of great interest within of the cathedral are the 'Papamoscas' ("Flycatcher"), an articulated statue which opens its mouth upon the sounding of the bells every hour, the Romanesque sepulchre of Mudarra, the vengeful stepbrother of the death of the seven princes de Lara (brought to the cathedral from its original location in the Monastery of San Pedro de Arlanza due to its abandonment by alienation), the carved chairs of the choir, the sepulchre of the Bishop Mauricio, the tomb of El Cid and his wife Doña Jimena, the letter of security of El Cid and his chest.
Strme fiale, pri katerih je razviden nemški vpliv, so bile dodane v 15. stoletju in so delo Juan de Colonia.