It’s hard to refrain from that involuntary gasp of awe and wonder when first stepping through a tawny stone portal into Siena’s Piazza del Campo. Magnificent medieval buildings rim the fan-shaped piazza and its hubbub of lively outdoor cafés.

Almost instantly the eye is drawn to the flooring – an outlay of nine massive triangular brick segments separated by veins of travertine. Converging as they follow the gentle slope of the piazza, the segments join at the entrance of the impressive Palazzo Pubblico (c.1297), the age-old seat of Siena’s civic headquarters. While beautiful to behold, this scene is more than an architectural masterpiece.