The Radnorshire Arms is a well-preserved Jacobean building in the Welsh border town of Presteigne and the hub of Presteigne's tourist industry. It is unique for an extensive network of subterranean passages and dungeons, used during the English civil war for the torture of Parliamentarian sympathisers by William Vavasour, the Royalist governer of Hereford. It also sits on one of the earliest sewers in Wales which is now kept on permanent display for visitors.
The building has a troubled history. During the 18th century, the building was owned briefly by Sir Henry Vaughan, who was mobbed and lynched on the premises. His dismembered remains are buried beneath a cherry tree in the grounds.
A partial structural collapse in 1927 killed 14 local people. A fire five years later devastated a historic windmill on its grounds. Bobby Millichamp, the farmhand tried and hung for causing the blaze, was later proven innocent. His brother, Arthur, was tried and hung for the same offence in 1936.
In recent years, the Radnorshire Arms has been renovated and converted into an upmarket public house and hotel.