The Ruin can be visited
Piercefield House (Ruin)

In Chepstow, Monmouthshire, Wales, stands Piercefield House, now a ruin, once a manor and country house. It is at an elevation of approximately 103 meters above sea level.
History+
The estate was first mentioned in the 14th century under names such as Peerfield. Until the 18th century, it was owned by the Walter family. In 1630, John Walter built the original house, which was expanded around 1700. In 1727, the estate changed hands for £3,366, going to Thomas Rous. His son sold it in 1740 for £8,250 to Colonel Valentine Morris, whose son Valentine Morris lived there from 1753 and had the park laid out. Through gambling, Valentine Morris lost his fortune and had to sell Piercefield in the 1770s. In 1785, banker George Smith acquired the estate for £26,200 and had a new three-story stone building erected in 1792. Financial difficulties also forced him to sell in 1794.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 51.6578, -2.6837