Floors Castle, in Roxburghshire, south-east Scotland, is the seat of the Duke of Roxburghe. Despite its name it is an estate house rather than a fortress. It was built in the 1720s by the architect William Adam for Duke John, possibly incorporating an earlier tower house. In the 19th century it was embellished with turrets and battlements by William Playfair for Duke James. Floors has the common 18th-century layout of a main block with two symmetrical service wings. Floors Castle stands by the bank of the River Tweed and overlooks the Cheviot Hills to the south.
Floors Castle is now a category A listed building, and the grounds are listed in the Inventory of Gardens and Designed Landscapes, the national listing of significant gardens in Scotland. It is open to the public. The castle featured in the 1984 movie Greystoke: The Legend of Tarzan, Lord of the Apes. The castle was featured on an episode of "An American Aristocrat's Guide to Great Estates" on the Smithsonian Channel and Amazon Prime Video. It first aired in 2020.