Idaho Code § 67-4614
The local governing body of any county or city may adopt an ordinance designating one (1) or more historic properties on the following criteria: historical, architectural, archeological and cultural significance; suitability for preservation or restoration; educational value; cost of acquisition, restoration, maintenance, operation or repair; possibilities for adaptive or alternative use of the property; appraised value; and the administrative and financial responsibility of any person or organization willing to underwrite all or a portion of such costs. In order for any historic property to be designated in the ordinance, it must in addition meet the criteria established for inclusion of the property in the national register of historic places. For each designated historic property, the ordinance shall require that the waiting period set forth in section 67-4615, Idaho Code, be observed prior to its demolition, material alteration, remodeling or removal. The ordinance shall also provide for a suitable sign or marker on or near the property indicating that the property has been so designated; provided however, that nothing in this chapter shall authorize or be construed to allow the designation, regulation, conditioning or restriction by ordinance or other means of any property or facility owned by the state of Idaho.
Idaho Code § 67-4614