To the left is the stately Maest?  (Madonna Enthroned; 1315) and to the right, Guidoriccio da Fogliano (1328, but whose authenticity has recently been disputed), depicting the Sienese captain's ride to a historic victory at Montemassi in the nicely detailed Tuscan landscape, notice the little Chianti vineyard in the military encampment.
To the left is the Van Gogh, on the right is the Mona Lisa, and to the right, Monet.