California Code, Civil Code - CIV § 1008

No use by any person or persons, no matter how long continued, of any land, shall ever ripen into an easement by prescription, if the owner of such property posts at each entrance to the property or at intervals of not more than 200 feet along the boundary a sign reading substantially as follows: “Right to pass by permission, and subject to control, of owner: Section 1008, Civil Code.”