A "Hidden Room" refers to a concealed space within a building that is not easily visible or accessible. These rooms can be found in various structures, including homes, castles, and historical sites. They often serve specific purposes, such as storage, secret meetings, or protection from intruders. The design of hidden rooms can vary widely, with some being cleverly disguised behind bookshelves or false walls. They have captured the imagination of many, often appearing in literature and films, where they are associated with mystery and adventure. Examples include secret passages and trapdoors that lead to these elusive spaces.