Interior view
by RIAÑO, Diego de, Photo
Riaño built the main sacristy as a Greek cross inscribed in a square, articulated to the height of the cornice by Corinthian pilasters and half columns in a Greco-Roman style that reflects the influence of Diego de Siloe at Granada Cathedral. Above, the square is transformed into an octagon to support the dome.
The photo shows the interior of the dome.