Wimpole Castle, lies on the grounds of the Wimpole Estate next to the village of Arrington in the county of Cambridgeshire in England.
Although this may look like a real castle ruin, it isn't. It is a folly; a ruin built primarily for garden decoration.
In 1751, the then owner of Wimpole Hall, Philip Yorke, 1st Earl of Hardwicke, commissioned Sanderson Miller (a noted follies architect in that time) to design the folly as a ruined Gothic medieval castle.
In 1769 it was finally built by Capability Brown, a famous English landscape architect. It is situated on a hill within clear sight of the back of Wimpole Hall.
At present the Wimpole Estate is owned by the National Trust and the castle ruin can be visited freely during opening hours. So this may not be a real castle but I think it is very convincing and I like it a lot. Also the walk to the ruin through the grounds of the estate is very nice.