the sculpture of Two Slaves by Michelangelo ; Leonardo da Vinci 's Mona Lisa ( La Joconde ) and Virgin of the Rocks ; Titian 's voluptuous Woman at Her Toilet and somber Entombment of Christ ; the poignant Old Man and His Grandson of Ghirlandaio .
Da Vinci 's Virgin of the Rocks is also known as the Madonna of the Rocks .