Thornewood is an estate in what is now Lakewood, Washington. It consists of three buildings, including Thornewood Castle, which was built from the brick of a dismantled 15th-century house imported from England. The Castle was used as a set for the Stephen King film Rose Red.

Several exterior shots of the castle was also used in the popular Netflix horror show The Haunting of Bly Manor.

The property was listed on the National Register of Historic Places in 1982 and is currently a bed and breakfast, vacation, wedding, and event rental facility.