Horsted Keynes is a village and civil parish in the Mid Sussex District of West Sussex, England. The village is located about north east of Haywards Heath, in the Weald. The civil parish is largely rural, covering , and has a population of 1,507 persons (2001 census).
The Prime Meridian passes to the east of Horsted Keynes.
Guillaume de Cahaignes, one of the French knights who'd landed with William, the Norman conqueror and fought at Hastings (and Lord of the Manor of what is now Cahagnes) was given Milton in Buckinghamshire and the Sussex village of Horstede (The Place of Horses in Saxon) which became Horstede de Cahaignes and in time Horsted Keynes. The place-name is first attested in the Domesday Book of 1086. The village has been formally twinned with the Normandy village of Cahagnes since 1971. The Horsted Cahagnes Society promotes social and cultural links, and organises annual exchange visits between the two communities.
Horsted Keynes is centred on a village green with pubs, Post Office and village store. The Post Office was to be closed down for lack of use but was bought up by a group of villagers who invested in its continued use for the community. It now serves a large rural area.
A couple of months before being assassinated, U.S. President John F. Kennedy slept in the parish when he stayed one Saturday night at Birch Grove, the home of the former Prime Minister, Harold Macmillan. The American Secret Service closed the village that night, siting their communication hub in the Lounge Bar of "The Crown Inn".
The two principal churches are: the Anglican Parish Church dedicated to St Giles and the Roman Catholic church of St Stephen which is unoccupied and controlled from the nearest town, Haywards Heath. Harold Macmillan was buried in the churchyard of St Giles after his death in December 1986, alongside his wife Dorothy, who died 20 years previously.
The railway station, three-quarters of a mile from the village, is now owned and operated by the Bluebell Railway, which is largely run by volunteers and operates using vintage steam trains. The station originally also had a connection with Haywards Heath, between 1883 and 1963.
On 1 July 2003 a lightning bolt struck the electricity pole beside The Crown public house on the village green which has stood there for at least 300 years and probably much longer. The roof and much of the building were destroyed in one of the largest fires in the area for many years. Fortunately the fire did not spread to the petrol storage tanks of the adjacent Crown Garage. A smaller incident occurred in May 2007 when a telephone pole was struck, removing communications from much of the village. Several homes in Lewes Road were left without a telephone service for over one month whilst permission was sought to dig on private land to relay a cable.
Like many other English villages Horsted Keynes is losing businesses that have been there for many years. After the closure of the main village store "Sayers and Carter" in 1992, and the more recent loss of the butcher "Maynards", followed by the village hairdresser and photographer, the village garage closed down in June 2007. It was only 20 years ago that the village had two garages, now it has none, leaving the nearest petrol retailer more than away. Planning permission was granted and the garage site has now been turned into residential accommodation.
This part of Sussex was known for its iron industry long before the industrial revolution and the coming of the railways. Little remains of this now, except for the hammer ponds and other traces of this activity dotted around the surrounding countryside, although iron working is remembered in many local place names.