The Fresco of Guidoriccio da Fogliano in the Sala del Mappamondo, Palazzo Pubblico, Siena (c. 1330)

The end wall of the Sala del Mappamondo, opposite to the wall containing Simone's Maestà, is entirely covered by this fresco depicting the famous commander Guidoriccio with defeated fortresses in the background.

This painting had always been considered the greatest example of Simone's artistic excellence. However, after discovering a fresco below the equestrian figure (a very beautiful one and certainly much older), the Guidoriccio painting was re-attributed by some experts to a much later artist. The controversy that followed this re-attribution has not yet been settled.

The figures in the niches on both sides are the patron saints of Siena, painted by Sodoma, an excellent Sienese master of the sixteenth century.