California Code, Government Code - GOV § 25373

(a) The board of supervisors may acquire property for the preservation or development of a historical landmark. The board of supervisors may also acquire property for development for recreational purposes and for development of facilities in connection therewith.

(b) The board may, by ordinance, provide special conditions or regulations for the protection, enhancement, perpetuation, or use of places, sites, buildings, structures, works of art and other objects having a special character or special historical or aesthetic interest or value.These special conditions and regulations may include appropriate and reasonable control of the appearance of neighboring private property within public view.

(c) Until January 1, 1995, subdivision (b) shall not apply to noncommercial property owned by a religiously affiliated association or corporation not organized for private profit, whether incorporated as a religious or public benefit corporation, unless the owner of the property does not object to its application. Nothing in this subdivision shall be construed to infringe on the authority of the board of supervisors to enforce special conditions and regulations on any property designated prior to January 1, 1994.

(d) Subdivision (b) shall not apply to noncommercial property owned by any association or corporation that is religiously affiliated and not organized for private profit, whether the corporation is organized as a religious corporation, or as a public benefit corporation, provided that both of the following occur:

(e) Nothing in this subdivision shall be construed to infringe on the authority of any legislative body to enforce special conditions and regulations on any property designated prior to January 1, 1994, or to authorize any legislative body to override the determination made pursuant to paragraph (2) of subdivision (d).