extract from:
Exploring the Ridgeway by Alan Charles
‘... The cleaning of the horse (the scouring) was an important part of the open-air festivals that took place on the hill at intervals of seven years or so until 1857. These were great occasions for games, competitions, dancing, singing and drinking. It was reported that 30,000 people atened the festival in the year 1780. A local saying tells us that ‘while men sleep, the Horse climbs up the Hill’. This is not as outrageous as it sounds, for as the soil falls away from the upper edges and exposes more of the chalk, and the lower edges silt up and become colonized by grass, so the horse does indeed climb the hill!