Believed to have started around 1650 AD, "this horse race is held twice each year on July 2 and August 16 in Siena (Italy), in which ten horses and riders represent ten of the seventeen Contrade, or city wards. A magnificent pageant precedes the race, which attracts visitors and spectators from around the world." This clip is from "Desmond Morris' The Human Animal". (There was another clip back in July 2008.)