Horses are led by the "Barbarescos" of each parish at the end of the fifth of six trial horse races in Del Campo square in Siena August 15, 2013. Every year on July 2 and August 16, almost without fail since the mid-1600s, 10 riders compete bareback around Siena's shell-shaped central square in a bid to win the Palio, a silk banner depicting the Madonna and child. [Photo/Agencies]