absent probable cause. History The Fourth Amendment protects "persons, houses, papers, and effects". In modern cases, the Supreme Court interprets "a house" to mean "a home and its curtilage". It is not obvious when the Court first equated "house" with "home", though Prigg v. Pennsylvania (1842) seems to assume that "house" means "home". The first uses of the term "curtilage" by the Supreme Court appeared in the decisions of two unrelated cases from 1864. United States v. Stone (1864), involved a boundary dispute over Fort Leavenworth, as to "what lands properly belonged to this military post, and the proper curtilage necessary for the use and enjoyment of it". In Sheets v. Selden's Lessee (1864), the Court referred to "a grant of a messuage or a messuage with the appurtenances will carry the dwelling-house and adjoining buildings, and also its orchard, garden, and curtilage." Application The Supreme Court holds that the Fourth Amendment protects homes and their curtilage from unreasonable searches without a warrant. However, curtilage is afforded less protection than a home. Absent "No Trespassing" signs or fences with locked gates, it is considered reasonable for a person (including a police officer) to walk from a public area to the obvious main entrance to the home using the most obvious path in order to "knock and talk" with a resident. But otherwise, government agents need consent, a warrant, or probable cause of exigent circumstances to enter a home's curtilage. Many state constitutions have clauses similar to the Fourth Amendment of the U.S. Constitution, and many have "castle laws" which use the term "curtilage". Although states are entitled to interpret their definitions different from (and subordinate to) the U.S. Fourth Amendment, they generally interpret "houses" the same way as does the Supreme Court, including its definition of "curtilage". In UK listed-building legislation The concept of curtilage is relevant to town and country planning in the United Kingdom, particularly as it relates to listed building legislation. The consideration afforded to a listed building may extend to other structures or landscape within the curtilage of the primary structure, if the item(s) in the curtilage is old enough, and physically attached to the main building or otherwise important to the setting of the structure. Current legislation uses a cut-off date of 1947, so that later additions, while they may be within the curtilage, are not included in the listing designation. The listing of a