Athelhampton (also known as Admiston or Adminston) is a 15th-century manor house in England. It is a privately owned country house on 160 acres (647,000 m²) of parkland, located five miles (8 km) east of Dorchester, Dorset. The house is now open for public visits. In 1086, the site was recorded in the Domesday Book which states that the Bishop of Salisbury, with Odbold as tenant, held the manor, then called Pidele. The name Aethelhelm appears in the 13th century, when Athelhampton belonged to the de Loundres family. In 1350 Richard Martyn married the de Pydele heiress, and their descendant Sir William Martyn, Lord Mayor of London in 1492, built the current Great Hall in or around 1485. He also received licence to enclose 160 acres (647,000 m²) of deer park and to fortify his manor. A West Wing and Gatehouse were added in 1550, but in 1862 the Gatehouse was demolished. Sir Robert Long purchased Athelhampton House in 1665 from Sir Ralph Bankes. In 1684 an attempt was made by the court to sequester the estate from the then owner, James Long Esquire (son of Sir James Long, 2nd Baronet), to recover a debt, but this appears to have been unsuccessful. The estate passed down through the Long family to William Pole-Tylney-Long-Wellesley (Viscount Wellesley, later 5th Earl of Mornington), who sold it in 1848 to George Wood. In 1891, the house was acquired by the antiquarian Alfred de Lafontaine, who carried out restoration to the interior and added the North Wing in 1920”“21. At the same time, de Lafontaine engaged Inigo Thomas to create one of England's great gardens as a series of "outdoor rooms" inspired by the Renaissance. Twenty acres (81,000 m²) of formal gardens are encircled by the River Piddle, and consist of eight walled gardens with numerous fountains and pavilions, plus a balustraded terrace, statues, obelisks and vistas through gate piers. Great Court contains 12 giant yew pyramids set around the pool by the great terrace. The lawn to the west has an early 16th-century circular dovecote, and the south terrace features a vast " Magnolia grandiflora" and a Banksian rose. Pear trees cover the old walls and support roses and clematis. Across the A35 stands the Church of St John, built in 1862 as a way of moving the old parish church away from the house. The church was designed by the Dorchester architect 'Hicks' who employed Thomas Hardy at the time. The Church was acquired with its pews and most of the Grave Yard in 1984 after the church had fallen into disrepair having been made redundant by the Church of England in 1975. The Church is now used by the Antiochian Orthodox parish of St Edward King and Martyr. A congregation meet at the church with services every Sunday. Athelhampton has been owned by three generations of the Cooke family, the present owners.
- The House was used as a location for the 1972 film, Sleuth, when it was owned by Robert Cooke, MP.
- The house and gardens were also used for the main filming location of the Doctor Who serial The Seeds of Doom .
- Julian Fellowes used the house for his children's film From time to time based on The Chimmneys of Green Knowe.