The White Horse, cut from chalk on the hillside approximately 1,000m north of the village of Alton Barnes, was commissioned in 1812 by Robert Pile or Pyle, a local tenant farmer. He paid John Thorne, a journeyman sign painter known as Jack the Painter, £20 to design and cut the horse. Thorne was evidently a rogue. Having copied the design of the Cherhill White Horse, east of Calne, which was cut in 1780, he pocketed an advance of the fee and decamped leaving a local resident John Harvey to carry out the actual work. Thorne was later convicted of a series of crimes and hanged.
The horse is 166ft high and 160ft in length. The disproportionate height is to prevent foreshortening when viewed from a distance. Over the years, elements of certain features of the horse have altered, and overall the horse is probably now slightly smaller than its original size. It requires regular periodic scouring and cleaning to prevent it being reclaimed by nature.
The Alton Barnes White Horse is one of eight surviving White Horses in Wiltshire, the most recent being the horse carved on Roundway Hill, north of Devizes, to celebrate the Millennium. Robert Pile, or a namesake, was also responsible for the Pewsey White Horse carved in 1785; the original carving of this horse was lost and it was replaced by a new horse in 1938. None of the Wiltshire White Horses predates the 18th century. Most of them seem either to have celebrated an event or simply to have been the whim of a local landowner. The origin of the symbol of a white horse which has become totemic of Wiltshire is obscure. Perhaps inspiration came from the prehistoric White Horse at Uffington, Oxfordshire, which dates back to around 1,000 BC and is the only ancient White Horse in the United Kingdom, but the Uffington horse is not only much larger – 360ft in length – but its fluent elongated design is quite different from the more modern Wiltshire horses.
The Alton Barnes White Horse is located on Milk Hill, the highest point in the county of Wiltshire at 295m in height, with the adjacent Tan Hill at 294m - there is in fact only 26cm difference. Milk Hill is the second highest chalk hill in the UK and was the starting point for longest hang-glider flight ever in the UK on 10th May 2011 by Nev Almond.